SOLUTION: ln(4x-5)+ln(x-3)=ln15

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Question 735805: ln(4x-5)+ln(x-3)=ln15
Answer by Susan-math(40) About Me  (Show Source):
You can put this solution on YOUR website!
Use the rule lna+%2B+ln+b+=+ln%28ab%29
so ln%284x-5%29%2Bln%28x-3%29=ln%28%284x-5%29%28x-3%29%29
so now you have
ln%28%284x-5%29%28x-3%29%29=ln15
so %284x-5%29%28x-3%29=15
4x%5E2-5x-12x%2B15=15
4x%5E2-17x=0
x%284x-17%29=0
x=0or x=17%2F4
but must omit x=0 since it has us take ln of a negative number when substituted into 4x-5 or x-3, so it is not in the domain.
so answer is x=17/4