SOLUTION: log base 3(2x+3) + log base 3 (X-2)=log base 3 72 what would the answer be in traditional

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Question 712321: log base 3(2x+3) + log base 3 (X-2)=log base 3 72 what would the answer be in traditional
Answer by nerdybill(7384) About Me  (Show Source):
You can put this solution on YOUR website!
log base 3(2x+3) + log base 3 (X-2)=log base 3 72
log base 3(2x+3)(X-2)=log base 3 72
(2x+3)(X-2)= 72
2x^2-4x+3x-6=72
2x^2-x-6=72
2x^2-x-78=0
rewrite the middle term:
2x^2+12x-13x-78=0
(2x^2+12x)-(13x+78)=0
2x(x+6)-13(x+6)=0
(x+6)(2x-13) = 0
x = {-6, 13/2}
throw out the negative solution (extraneous) leaving:
x = 13/2