ORDER OF OPERATIONS
We have to have a way to always simplify a problem. The order of what we do has to be the same all the time. PEMDAS is the method a mathematician uses.
P = perform the work INSIDE the PARENTHESIS first
E = perform the work with all powers or EXPONENTS next
M = MULTIPLICATION
either multiply OR divide as you work the problem from LEFT to right
D = DIVISION
A = ADD
either multiply OR divide as you work the problem from LEFT to right
S = SUBTRACT
Problem: Simplify: 2(4 – 1)^{2} – 6 ¸ (6 – 9) – 6 ¸ (10 – 8)
Solution:
P = perform the work INSIDE the PARENTHESIS first so we will perform (4 – 1), (6 – 9) and (10 – 6)
2(4 – 1)^{2} – 6 ¸ (6 – 9) – 6 ¸ (10 – 8)
2(3)^{2 }– 6 ¸ (–3) – 6 ¸ (2)
E = perform the work with all powers or EXPONENTS next so we’ll do the square exponent
(3)^{2} = 9
2(3)^{2 }– 6 ¸ (–3) – 6 ¸ (2)
2(9) – 6 ¸ (–3) – 6 ¸ (2)
M = MULTIPLICATION
either multiply OR divide as you work the problem from LEFT to right
D = DIVISION
This means we need to perform 2(9), – 6 ¸ (–3), and – 6 ¸ (2)
2(9) – 6 ¸ (–3) – 6 ¸ (2)
18 + 2 – 3
A = ADD
either multiply OR divide as you work the problem from LEFT to right
S = SUBTRACT
This means we have to perform the work from left to right so we’ll add (18 + 2) first then subtract three.
18 + 2 – 3
20 – 3
17
