How do I determine if this equation is a linear function or a nonlinear function?

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The easiest way I have for knowing the difference between linear and nonlinear is the exponent value on the variable * x*.

It is important to understand the root word in linear. It is LINE. A straight line, no curves.

For example:

y = 2* x* - 3 This is linear because the exponent on

*is one. Thus your slope is standard rise over run, like a stair step and simply goes up or down.*

**x**Y = * x*^2 + x + 4 is nonlinear. When graphed it becomes a parabola, which looks like a hill on your graph. This is because the exponent on the variable of

*is more than one.*

**x**This pattern continues on for all equations. Hope this helps to put it into easy to understand terms. :)

Well, if the expression of the function is like this:

f(x)=ax+b

then it is for sure a linear function.

So, all expressions, where it could be found the unknown x, but with the condition that the exponent of the unknown x, not to be bigger than 1, are expressions of linear functions.

Here's one suggestion/method I haven't seen mentioned yet: it's called the vertical line test. This method works well for lines and curves that are already graphed. The vertical line test states that if you draw a vertical line through the line or curve in question and the vertical line intersects the line or curve in only one place, then the line or curve is a function.

One thing I did not see mentioned in any of the above posts is this: a line that is vertical IS NOT a function. So all lines of the form x = a, where a is some number, are not functions. These lines are straight, but do not have a unique x value for each value of y, therefore, not a function.

Also, understand that a line or curve can be a function without being a linear function. For example, ax^2 +by + c = 0 is a function (quadratic function) but not a linear function.

**Hi,**

**How do I determine if this equation is a linear function or a nonlinear function? **

**Answer:**

**Points:**

**1) If the Power Of variable is 1, so the function is linear.**

**Example:**

**Y=mx+b and Y=ax+by+C **

**2)Generally In mathematics a, b,c are treated as a constant and x,y,z are treated as a variable. **

4) **If the Power Of variable is greater than 1, so the function is not linear.It can be Quardratic Function or other.**

**Thanks Alot.**

**From: Osama khan**

** **

if you have a table of values find your first differences. if your first diffs are the same it is linear. if not it is not linear.

The x has to have a power of 1

A linear function is in the form y = mx + b or f(x) = mx + b, where m is the slope or rate of change and b is the y-intercept or where the graph of the line crosses the y axis. You will notice that this function is degree 1 meaning that the x variable has an exponent of 1. If a function is nonlinear, then the exponent of the x variable would have an exponent of something other than 0 or 1. Another linear function is in the form of y = a or f(x) = a, where is any real number. The exponent of x in this function is 0 because x^0 = 1, ie y = ax^0 or y = 1x.

LINEAR MEANS SINGLE. WHEN A FUNCTION IS LIKE

f(x)=ax+b

then it is linear function becasue here expression 'x' raises to power '1' only such functions are linear functions and others where exponent 'x' have power greater than one these are non linear functions

linear means single

when a function is like

f(x)=ax+b

then it is called a linear function

a function like

f(x)=ax+b is a linear function

here expression 'x' have power=1

functions like

f(x)=ax^+bx+c

are non linear functions

Hello Schnoop,

Determining whether your equation is a linear or non-linear function can be achieved many ways. First off, are you looking at a graph of the function, or is it an equation you are looking at? If it is a graph, then the simplest answer is "Is the graph a straight line?" You see, linear means that all your variables are only to the first power, and when variables are only to the first power, their graphs will always make a straight line. Look at the word LINEar, and notice that the first part says "LINE". That's an easy way to remember linear=line when graphed.

In equation form, is the x, y, or whatever variables you are using to the power of 1, or first power? If you are looking at the equation and the variables are only to the first power, or in other mathematical words to the first degree, then your function is linear. In short, find all the variables and makes sure that they don't have any exponents attached to them other than a 1.

I hope this helps you, good luck :)

all linear functions are in the form

ax+by = c where a,b,c are real values and x,y are variables.

probably the easiest way for me is to plug in the equation on a graphing calculator and see if its linear

If an equation is a linear function then when graphed, it creates a line. Solve the equation so that it takes the form y=mx + b. m is going to be the slope of the equation and show how steep the line is. b will tell you where the y intercept is.

If the equation will not simplify into the y=mx+b form, it is not a linear equation, or you have made a mathematical error. Linear equations will never be raised to a power ie: x2 once simplified. Don't let an equation that IS raised to a power trick you though! Be sure to see if any terms cancel themselves out before you judge it to be linear.

To graph an equation, make a chart with your x and y values. Plug in values for x and then solve the equation and obtain the y value. Finally, chart the results on a coordinate grid to show the path of the line. You only need 2 points to make a line, but a third point is advised just to make sure you've really gotten a straight line!

Happy mathing! Good luck!

if you are presented with a table of values, you can determine that the function is linear if it has a constant rate of change, to test this you would take

f(xx)-f(x)/xx-x (This is supposed to be "(f of x-two minus f of x-one), divided by (x-two minus x-one)

-if you do this with multiple ordered pairs given in the table and you get the same answer each time, then you have yourself a linear function.

for example: you are given (1, 5) (2, 10) and (3, 15)

(10-5)/(2-1)= 5 and

(15-10)/(3-2)= 5

you have a constant rate of change is 5 and therefore this formula [f(x)= 5x] is a linear function

Find all the variables. If no variable has a power of >1, the function is lenear.

if it uses: y=mc+c, it is linear. A non-linear function will include powers/indices

linear function: y=mx+c, x has power 1

nonlinear: x has a power >2, for example, (x+a)(x+b) where if you expand it it becomes x^2 + bx + ax + ab

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Any equation having both the the degrees of both the variables as one can be called as a linear equation.Otherwise its a non linear equation.

However sometimes you encounter problems having dy/dx & dx/dy instead of x & y these equations are called as differential equations.

Its a single line

y=m(x)+b

A good way to tell if it is a linear function or not is to graph it. After graphing it, use the verticle line test to decide wether not it is a function. draw a line from top of the graph to the bottom, if the line crosses your verticle line more than once it is not a function.

another way to decide if it is or not is to make a table. if two x values are the same it is not a function.

you would graph your function first.

If it is a straight line then you know its a linear function.

But if it does not make a straight line it is a nonlinear function.

The best way is to use a ruler after you graph and see if its straight.

* more than or equal to 2 (not >2)

VLT, the vertical line test. Draw a line verticly through all the points graphed. If two points are on the same line, the entire equation isn't a linear function

if the x is to the power of one, it is linear(can be written in the form y=mx+b).

unless it Is a absolute value equation (y=|x| or some variation there of)

PS the vertical line test shows when something is a function, not whether it is linear or non-linear

when trying to determine if a given function is linear our not, look at the exponetial of the unknown. If it is NOT 1 then is is NOT linear. If it is exactly 1 then it is linear.

E.g. f(x) = a*x+b is linear. (no listed exponent, so we take it to be 1)

F(x) = a*x^2-b*x+c would be non-linear.

* more than or equal to 2 (not>2)

check out if the power of x is one

If it can fit the form Ax+By=C it is a linear function, this means no exponents in this form.

Linear equation means equation that plots straight lines on graph.It is of the form ax+by+c=0 where a,b,c are real numbers and x and y variables.

Linear functions come in the form y=ax+b

They are straight lines.

Quadratic functions come in the form y=ax^2 + bx + c

They are parabolas.

There are two ways by which we can test if a given equation is a linear function or not .

1) By Graph : I the graph of the equation is a straight line then the function is a linear function.

ii) By form of the equation : If the degree of the equqtion is one i.e. The power or the exponent of the variable is 1 then the equation is linear. In this case the equation will be in the form : y = mx + c [ where m is the slope of the line and c is the y- intercept ] .

If y=x+c it is linear regardless of the gradient.

If y＝x^z+c it is not a line. Hence the term non-linear. y=x^2 is a parabola.

Graphically, if the equation gives you a straight line thenit is a linear equation. Else if it gives you a circle, or parabola or any other conic for that matter it is a quadratic or nonlinear equation.

ALTERNATIVE:

If the highest power of x in the equation(in x) is 1 then it is a linear equation else if the power of x is greater than 1 then it is nonlinear.(ie IF AND ONLY IF THE COEFFICIENT OF x HAVING THE HIGHEST POWER IS NONZERO!!!)

A linear function will be a straight line with an x and y intercept and the** same slope through the whole**** line**.

A nonlinear function will not be a straight line and will have an indefinite slope.

the exponent value of x.

Well, if the expression of the function is like this:

f(x)=ax+b

then it is for sure a linear function.

So, all expressions, where it could be found the unknown x, but with the condition that the exponent of the unknown x, not to be bigger than 1, are expressions of linear functions.

if the variavle of the function has power 1 than the function is linear,

that is suppose the function is f(x) = a x^n + b x^m + ...

you check, if at least one of the power of "x" in the whole expression if not "1" then its non-linear, but if all the powers of "x" are either "0" or "1" then its linear.

examples:

1) f(x) = a x + b = a x^1 + b x^0, power of x are 1 & 0 so linear.

2) f(x) = a x + b x^(0.5), powers of x are 1 & 0.5 so non linear.

3) f(x) = a x^100 + b, powers of at least one of the x is 100 =/= 1 so non linear.

4) f(x) = a, power of x is "0" so linear.

it is not necessary that it has to be eqn in one variable.

a general 2nd degree eqn like ax^2 + by^2 + 2hxy +2gx +2fy+c=0

represents any curve( line, circle, para hyper bola etc). even if

ax^2 + by^2 =0 then also the eqn is second degree as max power is 2 in 2hxy where poer of x and y is one and1+1=2.

if even 2hxy=0 u can easily see that it becaomes a st line eqn.

If the rate of change is constant, then its linear but if its not constant, then its nonlinear.

I really do not get how to explain it, so here is an example and a worksheet that you can print out and pr ctice with!! You are welcome!! :)

**Sources:**

It's simple: The basic form of a linear function is f(x) = ax + b.

a = the constant

x = the variable

b = the y value

If a is not raised to any power greater than one, than the function is linear. However, for example, if the equation is:

f(x) = ax^2 + b

than the equation is no longer linear, but instead quadratic. It moves up from there, but as long as there are no exponants, your function is linear!

All linear functions are in the form

ax+by = c where a,b,c are real values and x,y are variables.

Does this help?

An equation is linear if its graph forms a straight line. This will happen when the highest power of x is "1".

Here are a few examples of linear equations:

3x + 2y = 8

y = 2x + 3

y - 2 = 3(x - 1)

(note: all variables are raised to the first degree)

Here are some examples of non-linear equations:

y = x^2 (note: x is raised to the second power)

x^2 + y^2 = 4 (note: both x & y are raised to the second power)

**An equation is linear if its graph forms a straight line. This will happen when the highest power of x is "1".**

The way how you differentiate a linear and a non linear function is as under-

In a linear equation the variables appear in first degree only and terms containing product of variables are absent.

e.g. y= 2x+3,

y= -3x+4,

3 y=2x-4 etc.

But in case of non linear equations at least one variable is not of the first degree or the equation contain product of variables.

e.g. y=x^2+2,

or, y^2=2x-4,

or, y=2x+3xy-4,

or, xy=1 etc.

``

Linear function is a 1st degree function, meaning the exponent of x is 1. Any exponent for x such as negative, positive that is greater than 1 is not linear.

examples:

y=2x + 1, since the exponent of x is 1 it is a linear function

y= 2x^3, since the exponent of x is 3 it is not linear function

y = 4, it is considered linear, since we can rewrite this as y =0x + 4

y=1/x + 2, it is not linear since x is at the denominator, we expresed in standard form it will become y =x^-1 + 2

y= 2x^(2/3) is not a linear since it has a fractional exponent that is not equivalent to 1.

The variable x must be either degree zero or degree 1 AND the variable y must be 1st degree in order to be a linear function.

Examples:

y = 2x - 3 (both x and y are 1st degree)

4x + 5y = 20 (both x and y are first degree)

2x - 4y = 7 + 3x (all variables are 1st degree)

y = -1 (x is degree zero and y is 1st degree; this makes a horizontal line which is a function of x)

If variable x is 1st degree but the variable y has a degree of zero, it will be a linear relation but not a function of x.

Example:

x = 4 (the graph is a vertical line and is not a function of x)

If variable y is 1st degree but the variable x has a degree other than 0 or 1, it will be a non-linear function of x.

Examples:

y = x^2 + 25 (x is not first degree)

y = 5x + 2 - x^3 (x is 3rd degree)

y = 1/x or y = x^(-1) (x is to the power of -1)

y = sqrt(x) or y = x^(1/2) (x is to the 1/2 power; the graph is 1/2 a sideways parabola)

y = 2^x (x is the exponent instead of the base, so the graph is exponential and not linear)

If variable y is not 1st degree, the relation will not be a function of x.

Example:

x^2 + y^2 = 4 (neither x nor y is 1st degree; the graph is a circle with a radius of 2)

x = y^2 (y is not 1st degree; this is a sideways parabola)

a linear equation is an application f : R -----> R ( R reals field)

verifies:

x, y `in` R `rArr` f(x) - f(y) = k ( x - y) where k is a costant.

If it is a linear equation, the highest power the you can see is 1 For example: y=2x-3, 3y=10x+8

non-linear equation can be quadratic, cubic, quartic equations

If the function is in the form of y=mx+b (m(slope)& b=constant ie. 1,2,etc) then its linear

whereas if its in y=ax^2 + bx +c : Quadratic

ax^3+bx^2+cx+d= Cubic

so all functions if they are not in the form of y=mx+b or y=5x+2 then they are not linear

for ex- y=4/x is not linear wherea y=4x is linear for c=0

This only works if you have graphed the equation, then use a Pencil Test to figure out if its a function or not.

Simply-

Line the pencil vertcially with the graph (parellel to Y-axis).

Run the pencil across the graph.

IF, at any point, the your graph touchs the pencil twice, then its NOT a function. If it doesnt, then it is a function.

A linear equation has the following form:

y = mx + b

where

m is the slope

b is the y-intercept.

You can also perform a vertical line test. If the line touches your graphed function in more than one spot, it is not a function.

y=mx+b form is linear and anything other than that is nonlinear

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