How do you solve the equation 3(x^2+2)=18?

2 Answers
Mar 20, 2018

2

Explanation:

x^2 +2=18/3

x^2 +2=6

x^2 =6-2

x^2=4

x=sqrt(4)

x=2

Mar 29, 2018

x = +-2

Explanation:

Given   3(x^2+2)=18    Solve for x

1) Divide both sides by 3
After you divide, you will get this:
x^2 + 2 = 6

2) Subtract 2 from both sides to isolate the x^2 term
x^2 = 4

3) Find the square roots of both sides
x = +-2

       . . . . . . . . Check . . . . . . .

Using the original equation, sub in either +2 or -2 in the place of x. The equation should still equal 18

3(x^2+2)=18

1) Sub in -2

3((-2)^2+2) should still equal 18

2)Square the -2
3 (4+2) should still equal 18

3) Add inside the parentheses
3 (6) should still equal 18

4) Clear the parentheses by distributing the 3
18  "does equal"  18

Check