SOLUTION: I'm having trouble with this problem, anyone know how to do it? -9(x-3)^2=-7

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Question 51197This question is from textbook Beginning Algebra
: I'm having trouble with this problem, anyone know how to do it?
-9(x-3)^2=-7 This question is from textbook Beginning Algebra

Answer by rchill(405) About Me  (Show Source):
You can put this solution on YOUR website!
First, divide both sides by -9 to yield +%28-9%28x-3%29%5E2%29+%2F+-9+=+-7+%2F+-9+. This simplifies to +%28x-3%29%5E2+=+7%2F9+. Now take the square root of both sides to produce +x-3+=+sqrt%287%2F9%29+. Adding 3 to both sides produces +x-3%2B3+=+sqrt%287%2F9%29%2B3+, which simplifies to +x+=+sqrt%287%2F9%29%2B3+. +sqrt%287%2F9%29+ is the same as +sqrt%287%29%2Fsqrt%289%29+, which simplifies to +2.64575+%2F+3+, so now we have +x+=+2.64575%2F3+%2B+3+, or +x+=+3.8819166+. To check our answer, substitute it into the original equation thusly: +-9%283.8819166-3%29%5E2=-7+. This simplifies to +-9%2A%28.8819166%29%5E2+=+-7+, which simplifies further to +-9+%2A+.77777688+=+-7+, which produces +-6.9999919+=+-7+. Because these number are extremely close, it means our answer of x = .8819166 is correct.