Was the addition property of equality appliedIn which step

Let f(x) = 3 − x . find the average rate of change of f(x) from x = a to x = a + h and simplify your answer so that no single factor of h is left in the denominator.

You have 138.72 in your saving account u take out 45.23 and 18.00 you deposit 75.85 into your account

Solve the triangle. a = 21°, c = 105°, c = 5