Direct, Inverse or Neither
Direct Proportion Graph
Inverse Proportion Graph
Equations
Word Problems
100
Tell whether the table represents direct, inverse or neither, if possible find the constant of variation
inverse, 24
100
Name two features of a Direct Proportion graph
Passes through the origin (0,0)
A straight line
Does not lie on the x or y axis
100
Describe an inversely proportional relationship
As one quantity decreases, the other increases in such a way that the product of the two quantities remains constant.
100
Direct, inverse or neither?
5y = 3x + 2
neither
100
If the (H) hours it takes to tile a floor is inversely proportional to the number of workers (N) on the job, what is the constant of proportionality if H=16 when N = 3
k = 48
200
Tell whether table C is represents an inverse proportion, direct proportion or neither.
neither
200
Describe how you can find the constant of proportionality from a direct proportion graph.
Choose a point on the graph and divide the y value by x
200
What is the constant of proportionality 
k=100
200
x+y=0
direct
200
In an inversely proportional relationship, what happens to X if you Double Y?
It is halved.
300
Direct y=5x
300
Write a direct proportion equation for this graph.
y=x
300
Write an inverse proportion relating speed and travel time.
st=100
300
0.1y = 4/x
Inverse proportion
300
Levels achieved in a computer game (Y) is directly proportional to gold coins collected X, find the missing value for A, write a direct proportion equation and find the constant of proportionality.
a = 90
y=1/18x
400
inverse y=100/x
400
What is the C.O.P for the graph on the left?
k=20
400
What does the point (20,5) represent?
If takes 5 hours travel time if you travel 20 m/ph
400
y/x = 0.4
Direct proportion
400
Mikey earned $50 in 4 hours, how much would he earn in 10 hours?
$125
500
inverse proportion
500
What does the point (100,2) represent?
At a temperature of 100K the volume is 2
500
If you travelled 100 mph, how long would it take in travel time?
1 hour
500
2y=k/x - 2
Neither
500
If y and x vary directly and the COP is 6 and y=9.6, what is the value of x?
1.6