Name: ____________________________________ Units: _______ Date: _______
Direct and Inverse Variation Review Handout
Write a function rule for the table.
1.)
x
2
3
4
5
f(x)
–8
–12
–16
–20
2.)
x
3
4
5
6
f(x)
7
8
9
10
Read the problem and answer the questions that follow.
3.) A zucchini plant in Darnell’s garden was 10 centimeters tall when it was first
planted. Since then, it has grown approximately 0.5 centimeters per day.
3a.) Write a rule to describe the function.
3b.) After how many days will the zucchini plant be 0.185 meters tall?
Write a direct or inverse variation equation.
4.) Write an equation of the direct variation that includes the point (9, –12).
5.) Suppose that y varies inversely with x. Write an equation for the inverse variation.
y = 6 when x = 8
6.) The amount of a person’s paycheck varies directly with the number of hours worked. For
16 hours of work, the paycheck is $124.00. How many hours would you have to work to make
$300?
7.) y varies inversely with x. Find the missing coordinate: (5, b) and (-4, -3).
Write a rule for the arithmetic sequence. Then find the 50th term.
8.) 9, 13, 17, 21, . . .
9.) 5, 5.3, 5.6, 5.9, . . .
Tell whether the data represents a direct variation, inverse variation, or neither. Write
an equation for the direct or inverse variation.
10.)
x
0
1
2
3
y
0
4
8
12
11.)
x
2
3
4
5
y
–6.6
–9.9
–13.2
–16.5
12.) An employee receives a weekly salary of $340 and a 6% commission on all sales.
12a.) Write a rule to describe the function f(d) that gives weekly earnings in terms of
d dollars in sales.
12b.) Find the employee’s earnings for a week with $660 total sales.
12c.) What were the employee’s total sales for a week in which her earnings were
$1300?
13.) The area formula for a parallelogram with area 36 is bh = 36. Does the formula represent
a direct or an inverse variation? Explain.
Answers:
1.) f(x) = -4x
2.) f(x) = x + 4
3a.) f(d) = 10 + 0.5d 3b.) 17 days 4.) y =

4
x
3
5.) xy = 48 6.) 38.7 hours
7.) b = 2.4 8.) A(n) =4n + 5; A(50) = 205 9.) A(n) = .3n + 4.7; A(50) = 19.7 10.) direct; y = 4x
11.) direct; y = -3.3x 12a.) f(d) = 340 + 0.06d 12b.) $379.60 12c.) $16,000 13.) Answers may vary; Inverse
because xy equals a constant 36.