How do you solve 8-8a^2=-792?

2 Answers
EZ as pi
Aug 15, 2016

a = +-10

Explanation:

8-8a^2= -792

8a^2 = 800

a^2 = 100

a = +-sqrt100

a = +-10

Jim G.
Aug 15, 2016

a=±10

Explanation:

What we want to do here is isolate the -8a^2 term on the left side of the equation while having the numeric value on the right.

To do this subtract 8 from both sides.

cancel(8)cancel(-8)-8a^2=-792-8

rArr-8a^2=-800

now divide both sides by -8

(cancel(-8)^1 a^2)/cancel(-8)=(cancel(-800)^(100))/cancel(-8)^1rArra^2=100

now take the 'square root' of both sides

sqrt(a^2)=±sqrt100rArra=±10

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