Question

Solve the following absolute value equation.
=
|x – 9|= 12
X=[?]
X =[?]

Answer 1

x = 21

x = -3

Explanation:

|x – 9|= 12

x - 9 = 12 and x - 9 = -12

x - 9 = 12

+9 +9

x = 21

x - 9 = -12

+9 +9

x = -3

Hope this helps!

Answer 2

`x= 21, \ -3`

Explanation:

`|x - 9|= 12`

square both sides:

`(x-9)^2 = 12^2`

simplify:

`x^2 -18x + 81 = 144`

`x^2 -18x + 81 -144= 0`

`x^2 -18x -63= 0`

take middle term:

`x^2 -21x + 3x -63=0`

take common terms:

`x(x -21) + 3(x -21)=0`

`(x+3)(x-21)=0`

solutions:

`x= 21, \ -3`