Question

Solve 5^x=81. 2Round to the nearest ten-thousandth. X≈????

Answer 1

Is that 5^x=81.2?

5^x=81.2  take the natural log of both sides

xln5=ln81.2  divide both sides by ln5

x=ln81.2/ln5

x≈2.7320  (to nearest ten-thousandth)

If you just meant 5^x=81, the process is the same

5^x=81  take the natural log of both sides

xln5=ln81  divide both sides by ln5

x=ln81/ln5

x≈2.7304  (to nearest ten-thousandth)