PEMDAS
(Order of Operations)
(Order of Operations)
The rule that lets you know which operation to perform first
Order of operations
A mathematical statement that contains algebraic expressions and symbols.
Open sentence
The answer to
2.4 : 3.6 = k : 1.8
k = 1.2
Formula for percent change
difference : original amount = x : 100
The answer to
x - 12 > 8
x > 20
The answer to
6 ÷ 2 (1 + 2)
1
A number is equal to 7 times itself minus 18
x = 3
The middle terms of a proportion
Means
Original: 200
New: 240
Find the percent change
20%
The answer to
-3/7x < 21
x > -49
The answer to
3(24 ÷ 2 - 3 x 4 +2 x 6)
36
The set of elements from the replacement set that make an open sentence true
Solution set
The first and last terms of a proportion
Extremes
Original: 20
New: 23
Find the percent change
15%
The answer to
6y > 5y + 21
y > 21
The answer to
2 + 15 ÷ 3 - 2 x 3 + 10
11
The answer to
(11q − 5) 2 − (10q − 1) 2 − (3q − 20) (7q + 10) = 124
q = -5
The answer to
10 : 15 = 4 : x - 5
x = 6
Sam pays $85 each month for his car insurance. If he earns a discount of 20%, how much will he pay each month?
$68
A more concise way of writing a solution set
(Ex: {x l x > 20 l}
Set-builder notation
The answer to
-10 ÷ (20 ÷ 2² × 5 ÷ 5) × 8 - 2
-18
The answer to
5 ∣ x + 3∣ − 4 = 8 ∣ x + 3 ∣ − 4
x = -5/3
x = -8/3
The answer to
2n - 4 : 5 = 3n + 3 : 10
n = 3.6
Emma is purchasing wire and beads to make jewelry. Her merchandise is $28.62 before tax. If the tax is 7.25% of the total sales, what is the final cost?
$30.69
|x − 165| ≤ 7.
How many integer values are included in the range?
15