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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