8. Module 1 Lesson 9 Proportional Relationships and Equations.notebook
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December 15, 2016
b. Write the equation that will relate the miles driven to the number
of gallons of gas.
Steps to figure out the equation.
1. Which unit is the dependent variable?
2. Which unit is the independent variable?
3. Find the k.
Constant of Proportionality = k =
4. Plug in the value of k to y = kx.
The constant
x is known as the independent
variable and
y as the dependent variable,.
11. Module 1 Lesson 9 Proportional Relationships and Equations.notebook
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December 15, 2016
a. Write several ordered pairs from the graph
and explain what each coordinate pair means
in the context of this graph.
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(0,0) ‐ It takes Andrea 0 hours to draw 0 portraits
(2,3) ‐ It takes Andrea 2 hours to draw 4 portraits
(4,6) ‐ It takes Andrea 4 hours to draw 6 portraits
(6,9) ‐ It takes Andrea 6 hours to draw 9 portraits
Tap
16. Module 1 Lesson 9 Proportional Relationships and Equations.notebook
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December 15, 2016
Closing Question
How can unit rate be used to write an equation
relating two variables that are proportional?
The unit rate is the constant of proportionality, k. After
computing the value for k, it may be substituted in place of k in
the equation y = kx. The constant of proportionality can be
multiplied by the independent variable to find the dependent
variable, and the dependent variable can be divided by the
constant of proportionality to find the dependent variables.