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Math 7 Unit 6 Study Guide
Name______________________________
Values that Vary
Period___________________
1. What is the equation for direct variation? __________________________
2. What equation would you use to find the constant (k) for direct variation? ________________
3. What is the equation for inverse variation? _________________________
4. What equation would you use to find the constant (k) for inverse variation? _______________
5. What is the formula for inverse variation proportion? _____________________
6. Write the product rule for inverse variation. ____________________
7. If you are given a table of values of x and y, name two ways you can you tell if the relationship is
a representation of direct variation? a) __________________________________
b) ______________________________
8. If you are given a table of values of x and y, name two ways you can you tell if the relationship is
a representation of inverse variation? a) __________________________________
b) ______________________________
9. What does the graph of an Inverse variation look like?
a)_____________________________ b)________________________________
10. What does the graph of a direct variation look like?
a)______________________________b)________________________________
11. The following 4 coordinates are points on a coordinate plane: (2, 3), (1, 6), (3, 2), (6, 1). Do the
connected points represent a direct variation, inverse variation, or neither?
Why?
__________________________________
__________________________________
__________________________________
__________________________________
_____________________________
12. x varies inversely with y. If x=8 when y=2, what is the value of y when x=4?
13. What type of variation is y=
100
? ________________________________
x
14. The Georgia lottery has $20,000,000 to award recipients. It gives each winner the same amount
of money. How would you decide how much money each recipient receives? Is this an example
of a direct or inverse variation?
______________________________________________________________________________
_______________________________________________________________________________
_______________________________________________________________________________
What is the equation that you would use for this situation? _______________________________
15. Sean makes $10.00 per hour. What equation would you use to determine how much money he
could make? _______________________________
Is this an example of a direct or inverse variation? ______________________________
16 .
Determine if the tables below represent inverse or direct variation or neither. If a type of
variation exists, write the equation of variation under the table.
The variables x and y vary directly. Use the given values to write an equations that relates x and y.
Fill in the values for y in the chart provided and graph the points and connect them with a line.
17.
y=2x
X
18.
Y= 1/3x
X
Y
-2
-6
0
-3
1
0
2
3
3
6
Y
The variables for x and y vary inversely.
Use the given values to write an equation that relates x and y.
Fill in the chart provided and graph the points and connect them with a line.)
19.
X
Y
-6
-2
-3
-4
-2
-6
2
6
3
4
6
2
Find each equation of direct variation, given that y varies directly with x
20 y = 10 when x = 2
22. y = 15 when x = 5
21.
Y = 42 when x = - 6
23.
y = 15 when x = 30
24. Can the graph of an equation show both a direct variation and an indirect variation on the
same graph?
Why or why not?