SOLUTION: {{{ log3 (x-9) + log3 (x-3)=2 }}}

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Question 945331: +log3+%28x-9%29+%2B+log3+%28x-3%29=2+
Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
solve for x
+log3+%28x-9%29+%2B+log3+%28x-3%29=2+
+log%283%2C%28%28x-9%29%28x-3%29%29%29=2
3^2=(x-9)(x+3)
9=x^2-6x-27
x^2-6x-36=0
solve by quadratic formula:
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
a=1, b=-6, c=-36
ans:
x=-3.7 (reject)
or
x=9.7