Addition
7 + 3 = ______
7 + 3 = 10
9 – 4 = ______
9 – 4 = 5
What is the equation of a proportional relationship?
y = kx
10 × 2 = ______
10 × 2 = 20
36 ÷ 2 = ______
36 ÷ 2 = 18
4 + (-6) = ______
4 + (-6) = -2
10 – (-4) = ______
10 – (-4) = 14
What is the equation for the unit rate?
k = y/x
(-8) × 3 = ______
(-8) × 3 = -24
40 ÷ (-5) = ______
40 ÷ (-5) = -8
(-9) + (-6) = ______
(-9) + (-6) = -15
(-4) – (-1) = ______
(-4) – (-1) = -3
What are the two things that must be true for a relationship to proportional?
(hint: think about graphs)
1. The relationship must be constant
2. The line must pass through the origin
(-1) × (-6) = ______
(-1) × (-6) = 6
(-56) ÷ (-7) = ______
(-56) ÷ (-7) = 8
In Buffalo, New York, the temperature was -14°F in the morning. If the temperature dropped 7°F, what is the temperature now?
(Hint: use addition)
(-14) + (-7) = -21
A submarine was situated 450 feet below sea level. If it descends 300 feet, what is its new position?
-450 - 300 = -750 ft
Do these ratios form a proportion?
6¢ per 14 customers
4¢ per 7 customers
6¢ per 14 customers
k = y / x
k = 6 / 14 = (3/7)
4¢ per 7 customers
k = y / x
k = 4 / 7 = (4/7)
No, the ratios do not form a proportion because they do not have the same constant rate.
Lilly bought 4 pairs of blue jeans at $32 each. How much money did she pay the clerk?
$32 x 4 = $128
The population in a town has decreased by 300 residents over the past 5 years. The same number of residents left each year.
What was the change in the town's population each year?
-300 ÷ 5 = -60 residents
6 × (5 + 3)
6 × (5 + 3)
6 × (8)
48
3 × (-4 - 6)
3 × (-4 - 6)
3 × (-10)
-30
Akeelah grew 6 flowers with 3 seed packets. How many seed packets does Akeelah need to have a total of 8 flowers in his garden? Assume the relationship is directly proportional.
k = y / x
k = (6 / 3)
k = 2
y = kx
8 = 2x
x = (8 / 2)
x = 4 seed packets
4 + 2 × 3
4 + 2 × 3
4 + 6
10
30 ÷ 5 × 3
30 ÷ 5 × 3
6 × 3
18