How do you solve $(3x+2)^2=9$ ?

Question

4385 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2016-07-06T15:38:44

$x = 1/3, -5/3$ These are all of the solutions, but if you consider only the positive square root, then $x = 1/3$ is the solution.

Take the square root of both sides

$sqrt((3x+2)^2) = sqrt9$

The square root of a value squared is that value and the square root of 9 is 3 and -3.

a) $3x+2 = 3$
b) $3x+2 = -3$

We have two equations since there are two values for the square root of 9. Isolate the variable and solve for $x$ .

a) $3x = 1$
$x = 1/3$

b) $3x = -5$
$x = -5/3$

Solutions are: $x = 1/3, -5/3$

How do you solve (3x+2)^2=9(3x+2)^2=9?