Square root property to solve equation: This one is a bit bigger: (3x+7)^2=8, show me how to do this please? :) The second part confuses me

Question

Square root property to solve equation:  This one is a bit bigger:  (3x+7)^2=8, show me how to do this please? :)  The second part confuses me

anonymous · Answer

you need to use square root? you can't do $(a+b)^2=a^2+2ab+b^2$ ?
and $\sqrt8=\sqrt{2\cdot4}=2\sqrt2$

anonymous · Answer

are you sure? wouldn't it just be sqrt2?

anonymous · Answer

but also you should remember that $\sqrt{x^2}=|x|$
yes i am sure i showed you that 8=2*4 and you can square root out of 4 so it leaves $2\sqrt2$

anonymous · Answer

Oh! ^^ okay! i see now, thank you :)

anonymous · Answer

what answer you got?

mathteacher1729 · Answer

The answer is not x = sqrt(2). See below for steps. (sorry, I'm too lazy to type them.) :-p