Proportional or Non-Proportional?
Proportional or Non-Proportional?
y = k x
Proportional
TRUE or FALSE: Proportional relationships MUST start at (0,0)
True
How do you find the y-intercept?
When x = 0, the y-value is the y-intercept.
Where the line crosses the y-axis.
What is the rate of change (m)?
y=2x+6
m = 2
Name two ways to solve for the percent of a number.
1. Part/Whole = %/100 and solve the proportion
2. Turn the % to a decimal and multiply
Proportional or Non-Proportional?
y = m x + b
Non-Proportional
How do you find the constant of proportionality (k) from a table?
k = y/x
How do you know if a graph has a positive or negative rate of change (m)?
Upward line = positive
Downward line = negative
What is m and what is b in the equation y = m x + b?
m = rate of change
b = y-interecpt
The manager of a coffee shop recorded how many customers ordered hazelnut coffee, vanilla coffee, and caramel coffee in one week. The results were:
Hazelnut- 10
Vanilla- 23
Caramel- 17
What percentage of customers ordered vanilla coffee?
46%
What is the difference between Proportional and Non-Proportional?
Non-Proportional: does not go through origin, rate of change instead of constant, has a y-intercept
What is the constant of proportionality (k)?
x y
3 12
5 20
7 28
k = 4
Describe what the graph of the line would look like:
y = 2x
The line would start at (0,0) and go through (1,2).
The line would have a rate of change of 2 (2/1).
Write the equation for the following:
An electricity company charges $0.12 per Kilowatt-hour.
y = 0.12x
The Adams family paid $210 for groceries. The family used a coupon for 20% off. What was the price the family paid after the coupon?
$168
Proportional or Non-Proportional?
Natasha has a job at the post office putting letters in envelopes. Natasha can put 42 letters in envelopes each hour.
Proportional
Write the equation from the table:
x y
-6 -1
0 -3
3 -4
9 -6
y = -1/3 x - 3
Draw the coordinate plane and plot the three points on the line for the following:
A recipe of trail mix requires 1.5 cups of nuts for every cup of dried fruit.
The line would start at (0,0) and go through (1, 1.5) and (2,3).
Write the equation for the following rate:
A family makes candied pickles for sale. A family packs 80 pickles per 5 jars.
y = 16x
The price of a laptop is 599.99. The sales tax rate is 8%. How much is the tax in dollars and cents?
47.92
Proportional or Non-Proportional?
Nicholas is buying shirts for his baseball team. He will pay $9.50 for each shirt plus a $22.50 delivery fee.
Non-Proportional
Write the equation from the table:
x y
-1 -11
1 1
3 13
5 25
y = 6 x - 5
If my line contains points (0,3) and (4,6) what is the rate of change?
3/4
Write the equation for the following:
Caleb practices playing the cello each day. He starts with a warm-up of 2 songs and then plays 6 songs each hour.
y = 6x + 2
Two pet stores are having a sale on dog toys.
Store A has the toys for sale for 1/4 of the original price
Store B has the toys for sale for 20% off the original price
If the toy is $40, which store has the better deal
Store A, for 30.00