Functions
Direct Variation
Intercepts
Equations
Graphing
100
An equation that has exactly one input for every output.
What is a function?
100
y=mx
What is the equation for direct variation?
100
Plug in 0 for x in an equation and get a point.
How do you find the y- intercept?
100
y = mx + b
What is the equation for slope intercept form?
100
Go over x units and up y units.
How do you graph a point?
200
Is this mapping a function?
Yes.
200
If y directly varies with x, what is the following constant of variation?
x = 16, y = 364
m = 22.75
200
Plug in 0 for y in an equation.
How do you find the x-intercept?
200
The change in y over the change in x.
(rise over run)
What is slope?
200
Where the graph crosses the x and y axis.
What are the x and y intercepts?
300
What is the value of the function f(x) = -4x + 7 when x=9?
f(x) = -29
300
The distance a car travels is directly proportional to time. If it covers 60 km in 2 hours, how far will it travel in 5 hours?
150 km
300
What is the y intercept for the following equation?
y = 4x + 2
(0,2)
300
What is the slope intercept form of this equation?
4x - 2y = 8
y = 2x -4
300
Find the slope of this graph:
m = 1/2
400
Does this table represent a function? 
No. There are 2 outputs for 2.
400
Heather’s weekly pay is directly proportional to the number of hours she works at the record store. Her pay is $174 for 24 hours of work. Find the amount of pay for 40 hours of work.
$290 for 40 hours of work.
400
What is the x intercept of the following equation?
4x - 2y = 12
(3,0)
400
The y value in the y intercept that is represented in an equation.
What is b in slope-intercept form?
400
Where does a graph for direct variation start?
At the point (0,0) or the origin.
500
What is the value for x in the function f(x) = 2x + 10 if f(x) = -14
x = -12
500
Solve this equation for y. Is it direct variation?
2x + 4y = 0
y = -1/2 x, Yes.
500
Surprise!
Find the slope of the line that passes through these two points.
(0, -2) (3, 6)
m = 8/3
500
What is the slope and y intercept for the following equation?
5x - 2y = 10
Slope: 5/2
Y intercept = (0, -5)
500
Graph the following equation:
6x + 3y = 18
The graph of y = -2x + 6
