Solving Exponential Equations (lacking a common base)

31^d=38

d = log 38/log31

d = 1.06

Step-by-step explanation:

31 ^ d = 38

Take log of both sides since the exponential equation have different base (always)

d log 31 = log 38

d = log 38 / log 31

d = 1.58 / 1.491

d = 1.06.

We can actually check to see if this is correct.

Substituting d = 1.06

31^ 1.06 = 38.092

(You see, that's approximately correct)

Keep learning, maths is fun!