SOLUTION: 17^-x-3 = 15^-8x solve for x using logarithms

           17-x-3 = 15-8x

      log(17-x-3) = log(16-8x)

  (-x-3)·log(17) = (-8x)·log(16)

Let log(17) = A
Let log(16) = B

        (-x-3)·A = (-8x)·B

         A(-x-3) = -8Bx

        -Ax - 3A = -8Bx

       -Ax + 8Bx = 3A

      x(-A + 8B) = 3A

              x = 

Replace A by log(17) = 1.230448921

Replace B by log(16) = 1.204119983

              x =  

              x = .4393147228

Edwin