Greetings from Brasil...
First we will solve the power:
(- 2)⁴ = (- 2)·(- 2)·(- 2)·(- 2) = + 16
rewriting our expression
15 + 48 ÷ (–2)⁴
15 + 48 ÷ 16
(the division / multiplication has priority over the addition / subtraction, so let's do the division first 48 ÷ 16 = 3)
15 + 3
18