How do you solve #2x^2-6=42#?

1 Answer
Will
Aug 19, 2016

#x=-2sqrt(6)# or #x=2sqrt(6)#

Explanation:

first move the #6# over
#2x^2=48#

then divide by 2
#x^2=24#

now take the square root
#x=sqrt(24)#

since x is squared in the equation then x can be negative or positive so we must remember to include this possibility when dealing with powers that are even
#x=-2sqrt(6)# or #x=2sqrt(6)#

you should then plug in the numbers and make sure they both work, which they do.

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