Respuesta :

Be sure to include the "=" sign:   f(x) = 2^x -7 

To find the x-intercepts, set f(x) = 0 and solve for x:  2^x - 7 = 0,
or
2^x = 7

Take the common log of both sides:  x log 2 = log 7
                              log 7
Solve for x:     x = --------- = 2.81 (approx)
                               log 2