You can determine the range and domain of a given equation by setting up tabular values.

For you to make a general statement about the domain of *x* values and the range of the *y* values, you have to plug in the values for *x* in order to obtain values for *y.*

Let's analyze the next equation:

f(x)=-x^2 + 2

f(x)=0 so -x^2 + 2=0

Plugging in values for x, we will see that is no restriction concerning the domain of x values, this one being all real numbers.

On the other hand, there is a restriction for y, so the range is going to be less or equal to 2.

x

......

-2

-1

0

1

2

.......

f(x)

-2

-1

2

1

-2

f(x)<=2

For example, you need to find the range of an equation, x^2+7

First, you must get the definition right. The range of the equation defines as a set of numerical values that the function (X) would used as x-values changes all the time.

You would get a range like this: X^2>=0.

Next, subtract negative 7 to both side of inequality equation so

X^2-7>=-7. This inequality equation shows that this X^2-7 would take any values that is bigger or equal to -7. So, the range would be like this (-7 and +infinite values).

The domain of this equation would be a positive set of x-values so domain is x^2>=0, more or equal to zero.