Properties of Equality
t - 8 ? 8 = 11 + 8
Addition
a + 4 = 4 ? 4 = a
Subtraction
y + 0 =1
y = 1
-9b = 9
b = 1
What is 45% of 80
36
x/10 ? = 5 x 10
Multiplication
y - 3 ? 3 = y
Addition
20 = v - 5
25
7 + b = 3
b = -4
5% of 20
1
x + 25 ? 25 = 25 - 25
Subtraction
2b ? 2 = b
Division
9 = x/3
x = 27
-4u + 10 = 2
u = -2
Find the discount price on a $10 t-shirt. It is 20% off.
$2.00
18/? = -3b/ -3
-3
v/9 ? 9 = v
Multiplication
26 = -5y + 6
y = -4
3(x + 3)= 18
x = 3
Find the discount price of a $50.00 outfit. It is 30% off.
$15.00
-16 x 4 = y/4 x ?
4
-15b ? (-15) = b
Division
-5(a + 2) = 30
a = -8
8x - 8 = -4x + 16
2
A $20 book is on sale for 15% off. Find the sale price.
$17.00