Answer:
a. 17 b. 51
Step-by-step explanation:
Follow Order of Operations (PEMDAS):
Parentheses, Exponents, Multiplication/Division, Addition/Subtraction
a. 9 + 4² - (4-2) • 4
9 + 4² - (4-2) • 4 –––Start with (4-2) = 2 (parentheses)
9 + 4² - 2 • 4 ––– 4² (exponents)
9 + 16 - 2 • 4 ––– 2 • 4 (multiplication)
9 + 16 - 8 ––– 9 + 16 (addition)
25 - 8 ––– 25 - 8 (subtraction)
17
b. 15 - 4 + 2(7-3) • 5
15 - 4 + 2(7-3) • 5 ––– Start with 2(7-3)
~ Note: this can be done using distributive property (2•7 - 2•3) OR solving the parentheses first and then multiplying 2(4). Both get 8 and same end result.
15 - 4 + 8 • 5 ––– 8 • 5 (multiplication)
15 - 4 + 40 ––– 15 - 4 (subtraction) *Note: Subtraction and addition are interchangeable in the order because you do it left to right*
11 + 40 ––– 11 + 40 (addition)
51