Use PEMDAS
5) -6(12 -15) + 2^3
Parenthesis first: -6(-3) + 2^3
Exponent: -6(-3) + 8
Multiplication: 18 + 8
Addition: 26
26 is the final answer for #5
6) -50 / (-10) + (5 - 3)^4
Parenthesis: -50/-10 + (2)^4
Exponent: -50/-10 + 16
Division: 5 + 16
Addition: 21
21 is the final answer for #6