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

2 Answers
Mar 20, 2018

Answer:

#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

Answer:

#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#