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Vocabulary
Tables
100
100
200
Proportions
Graphs
Y=kx
Wild Card
100
100
100
100
200
200
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200
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300
300
300
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300
300
400
400
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400
500
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500
500
Q: 100
What is an equation that
states two ratios are
equivalent?
Proportion
Q: 200
What is the point in the
center of a coordinate
plane?
A: 200
Origin
Q: 300
What are the numbers of
an ordered pair that
locate a point on a
coordinate graph?
A: 300
Coordinates
Q: 400
What is a value that does not
change?
A:400
Constant
Q:500
What is the symbol used to
represent a quantity that can
change?
A:500
Variable
Q:100
Does the
following table
represent a
direct
variation/prop
ortion?
X
Y
2
4
6
12
4
8
0
0
3
6
A:100
Yes! As the x-values increase, the y-values
increase! Hint: You may have to re-order
the numbers… but if you move an x, you
must move the y as well!
Q:200
Complete the
following
table for
1
y x
2
X
y
0
3
6
9
12
A: 200
X
0
3
6
9
12
y
0
1½
3
4½
6
Q: 300
Kaden can walk 1 mile in 10
minutes. Create a table of
values which represent time and
distance.
X- Distance
Y- Time
*Give 4 Coordinates!
A: 300
Answers may vary depending on groups!
Q: 400
What three characteristics
must be true for a table or
graph to represent a direct
variation?
A: 400
1. It is in y=kx form.
2. It always goes through the origin.
3. The constant (k) must be the same!
Q: 500
Determine the direct
variation/proportion
equation for the table
shown here.
X
Y
0
1
2
3
4
0
-3.5
-7
-10.5
-14
A: 500
Y = -3.5x
Q: 100
Set- up a proportion and solve the
following problem:
Johnny scores 27 points on three
basketball games. The season has 10
games. How many points can Johnny
expect to score by the end of the season?
A: 100
27 pts
xpts

3 games 10 games
27  10  270
270  3  90 pts !
Q: 200
Set up a proportion and Solve:
If y varies directly with x, and
y=34 when x=-17. Find x when
y=68.
A: 200
17 x

34 68
17  68  34* x
1156  34* x
34  x
Q: 300
Li mixes 3 units of red paint with
8 units of white paint to get
pink. How many units of red
paint should she mix with12
units of white paint to get the
same pink shade?
A: 300
3red
x

8white 12 white
3 * 12 = 8 * x
36 = 8 * x
4 ½ units
Q: 400
Shane’s neighbor pledged $1.25
for every .5 miles Shane swims
in the charity swim-a-thon. If
Shane swims 3 miles, how much
money will his neighbor donate?
A: 400
$7.50
Q: 500
18 45

40 x
A: 500
45 * 40 = 18 * x
1800 = 18 * x
100 = x
Q:100
If you have a positive constant, your
graphed line will be in which two
quadrants?
A:100
Quadrants I and III
Q: 200
What is the point that all direct variation
graphs will pass through?
A: 200
(0, 0)
The origin
Q: 300
Determine whether the points given create a
direct variation.
(1, 3) (2, 6) (3,12) and (4,3)
A: 300
No, when you graph the points they do not
go through the origin. They also do not
have a constant.
Q: 400
Determine whether the points given create a
direct variation.
(2, 9) (3, 13.5) (4, 18) and (5, 22.5)
A: 400
Yes, when graphed they go through the
origin and have a constant of 4.5.
Q: 500
Find an equation and graph the variation
where y varies directly as x, when y=3 and
x=2.
A: 500
y= 1.5x
Q:100
X and y vary directly. When x=-15 and
y=60. Find the direct variation/proportion
equation.
A: 100
y= -4x
Q: 200
X and y vary directly.
When x= 20 and y= 100, find x when y= 500.
A: 200
x=100
Q: 300
Why do we say “find an equation which
relates x and y”?
A: 300
X and y are related by the constant,
therefore when we find the direct
variation equation/proportion we are
finding the link between them.
Q: 400
Which of the following is a direct variation
equation?
a. 17/y=x
b. x+2=19
c. x/2=y
d. 19-y=x
A: 400
C
Q: 500
Find the direct
variation/proportion
equation for the
following table.
X
Y
25
1
50
2
75
3
100
4
125
5
A: 500
y=1/25 x
Or
Y=.04x
Q: 100
True or False:
Graphs of Direct Variations/Proportions can
start in Quadrant I and end in Quadrant II?
A: 100
False
Q: 200
Sue gets paid $8 an hour. If she works x
hours during the week, write an equation
showing how much she will get paid. Let
y be that amount (that she gets paid).
A: 200
y=$8x
Q: 300
Give me two variables which would not
represent a direct variation/proportion.
Ex. Test grade/# of gallons your mom’s car
holds
A: 300
Answers may vary!
Q: 400
When one variable increases, the other
variable ________. When one variable
decreases, the other variable
________.
A: 400
Increases, Decreases
Q: 500
Explain how you know a table of values
represents a direct variation/proportion.
A: 500
A table which represents a direct
variation/proportion will have both x and y
values increasing/decreasing. The k’s will
also be the same for each set of
coordinates.