If two expressions have the same base what happens to the exponents when the expressions are multiplied

The total of this whole angle, which is represented by ∠ABD, measures 64°.

We are given that apart of this angle, ∠CBD measures 30°, so that'd mean that the other part of this angle, ∠ABC, would measure 34°.

This is because both angles ABC and CBD combined would equal a total of 64°.

So we set up the equation;

30 + x = 64

-30       -30

x = 34°, therefore ∠ABC = 34°.