Solve the following logarithmic equation log x logx 15 2 S
Solve the following logarithmic equation. log x+ log(x + 15) = 2 Select the correct choice below and, if necessary, fill in the answer box to complete your choice. A. The solution set is (Simplify your answer. Type an exact answer. Use a comma to separate answers as needed.) B. There is no solution.
Solution
given log x + log(x+15) =2
log(x*(x+15) ) = 2
x*(x+15) = 102
x2+15x=100
(x+20)(x-5)=0
x = 5, x=-20
