Page 436 - Algebra 1

Lesson Practice
Tell whether each relationship is an inverse variation. Explain.
(Ex 1)
a. 4y=x b. 3xy=9
c.
(Ex 2)
d.
(Ex 3)
e.
(Ex 4)
If y varies inversely as x and y = 3.5 when x = 20, find x when y = 10. _1
Write an inverse variation relating x and y when x = 8 and y = 2 . Then graph the relationship.
Sierra found an inverse relationship between her hourly pay rate and the number of hours she must work to earn a set amount. If she works 7 hours for $8 an hour, how long will she work at $10 an hour to earn the same amount?
Practice
Distributed and Integrated
Find the LCM.
1. 8mn4 and 12m5n2 2. _1 wx3 and _1 w2x6
(57) (57) 2 4
Tell whether each equation shows inverse variation. Write “yes” or “no”.
*3. y = _x *4. y = _3 (64) 11 (64) x
*5. Estimate If y varies inversely as x and y = 24 when x = 99, estimate the value of y (64) when x = 50.
6. What is the minimum and maximum number of books read over the summer by (48) 10 students: 10, 9, 8, 10, 1, 8, 11, 20, 9, 10?
7. Budgeting The cost of a cell phone plan includes a monthly fee plus a charge per (59) minute. The charge for 200 minutes is $50. The charge for 350 minutes is $57.50.
How much is the monthly fee and how much is the charge per minute?
Find the product.
8. (b + 2)2 9. (x - 8)(x + 2) Use the FOIL method.
(60)
(58)
*10. Multi-Step Darius drew a square on grid paper that covers 121 cm2. (61) a. Write an expression to find the side length.
b. Substitute known values into the equation. c. Find the side length.
d. In which unit is the side length measured?
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