How does this work for solving equations and formulas: ax-b= c for x I'm having problems with my algebra 1 work. I just don't understand it.

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mgyoung's profile pic

mgyoung | High School Teacher | (Level 1) Adjunct Educator

Posted on

ax-b = c 

Follow the same steps you would for following regular equations.  Since the opposite of - b is + b, start by adding b to both sides.

ax - b + b = c + b

ax = c + b

Now since x is being multiplied by a, do the opposite and divide both sides by a

(ax)/a = (c + b)/a

x = (c + b)/a

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efranklin30 | eNotes Newbie

Posted on

ax-b=c

1. The goal is to get x on a side of the = by itself. 

2. In the original equation we have ax-b so to get the b on the other side of the = we have to +b.

3. That then gives us the equation ax=c+b

4. Next we have to remember that ax isa multiplication problem of a times x. So to get a to the other side we will have to divide both sides by a.

5.we then get x=(c+b)/a

chaobas's profile pic

chaobas | College Teacher | (Level 1) Valedictorian

Posted on

Now we have the given equation as 

ax-b= c

 

[adding b on both side we have]

ax=c+b

[dividing both side by a, we get]

 

x= (c+b)/a

 

so the value of x is (c+b)/a

neela's profile pic

neela | High School Teacher | (Level 3) Valedictorian

Posted on

To solve a problem like ax-b=c for x, we normally have to go through the following steps.

Here a, b and c are numbers and x is an unknown oa variable.

ax-b=c is the equation to solve.

Add b to both sides.

ax-b+b=c+b.

Simplify:

ax=c+b.

Divide by a both sidesby a:

ax/a= (c+b)/a

x=(c+b)/a or

x=(b+c)/a is the solution.

Example : Solve 10x- 20 = 30.

Follow the above steps:

Add 20 to both sides.

10x-20+20 =30+20

Simplify:

10x=30+20 or

10x=50

Divide both sides by 10 :

10x/10=50/10.

Simplify:

x=5. So x=5 is the solution of 10x-20=30 by following the above steps.

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