Download 12_2 Direct Variation Puzzle Sheet_ALG

Part 1. For the dote in the toble, tell whether y varies directly with x.
If it does, write an equotien for the direct variation.
Part I Answers
y = -4.5x
y=3x
12
36
50
30
8
-36
17
51
7.5
4.5
20
60
180
-25 -15
15
60
y = -4x
y =0.6x
-90
-9
-36
-3 13.5
4
-16
not direct
variation
Part 2. Write an equation expressing direct variotion.
Then graph the equotion.
(ÿ y varies directly as x, and
y = 14cmwhenx= 8cm.
I
--22
y varies directly as x, and
y = 91bwhenx= 72 lb.
y varies directly with x, and
y = 60miwhenx= 12mi.
y varies directly with x, and
y = 40 in. whenx= 15in.
y is directly proportional to x,
and y = 916 when x = $16.
12
y is directly proportional to x,
andy = 8gwhenx= 28g.
y is directly proportional to x,
and y = 180° when x = -30°.
8
y varies directly as x, and
y= 95kgwhenx= 10kg.
6
The amount of jelly, y, is
directly proportional to the
4
amount of peanut butter, x.
Write an equation if y = 6 oz
2
when x = 10 oz.
@
The circumference, y, of a
circle varies directly with
-2
2
4
6
8
the diameter, x. Write an
equation if y = 220 ft when
x= 70ft.
4 6 ..... 10 2 8 11 14 2 7 ...... 3 13 11 1 13 2 12 5 14 9 6
(111111!!!1!!111!!11) .............
Linear Equations and Their Graphs:
Direct Variation Equations and Graphs
PUNCHLINE o Algebra ,, Book A
02006 Marcy Mathworks
7.9
Have
Would
Mos,
To Have?
For each exercise, write an equation expressing direct variation. Find your
equation in the answer column. Then use your equation to solve the
problem. Write the letter of the equation in the box above your solution,
y varies directly as x, and ÿ y varies directly with x, and
y = 10whenx=2.5. Find
y= 1201b when x= 50 lb.
yifx= 18.
Find yifx= 40 lb.
y varies directly as x, and ÿ y is directly proportional to x,
y=9cmwhenx= 15cm. ÿ and y=45whenx=$600.
Find y fix = 80 cm.
Find y ifx = $1000.
ÿ1ÿ
ÿrÿ
ÿ ÿ y =2.66x
ÿ
q7 ÿ y =0.44x
The amount of money earned on a job is directly proportional
to the number of hours worked. If 876 is earned for 8 h of
work, how much is earned for 34 h of work?
ÿvQlÿ ÿ
.. ÿ.
ÿ ÿ y = o./zx
The height that a ball bounces varies directly with the heightÿ
from which it is dropped. A certain ball bounces 22 cm when
dropped from a height of 50 cm. How high will the ball
bounce ff dropped from a height of 90 cm?
,.
ÿ ÿ Y = 0.6x
)tÿ
ÿ ÿ y = 1.8x
ÿ,ÿ
ÿ ÿy=4x
The amount of water wasted from a leaking faucet is directly
proportional to the time that the faucet leaks. If 96 oz of water
;ÿ_-ÿ
are wasted in 30 min, how much water is wasted in 5 min?
ÿ ÿ Y = 8.4x
O The number of pages that Klunk can read varies directly with
the time he spends reading. If he reads 13 pages in 25 min,
how many pages can he read in 2 h?
ÿ ÿ Y = 3.2x
ÿ ÿ y = 0.7x
The weight of an object on another planet varies directly with
ÿ ÿ u - 2 4x
its weight on Earth. A person who weighs 150 lb on Earth
ÿ ÿJ- "
would weigh 399 lb on Jupiter. How much would a 180-1b
tÿ
person weigh on Jupiter? Round to the nearest pound.
ÿ ÿ y = 0.064x
The weight of water in a person s body varies directly as
ÿ ÿ y = 9.5x
his/her body weight. The body of 170-1b person contains
ÿtÿ
about 119 lb of water. How much water is in the body of a
ÿ ÿ " - 0 52x
person who weighs 120 lb?
ÿ ÿ y - "
The number of ceramic tiles needed to cover a wall is directly
ÿÿ @ y = 3.8x
proportional to the area of the wall. If 180 tiles are needed for
(¢W0
100 square feet of wall area, how many tiles are needed for a
ÿ ÿ y = 0.075x
Linear Equations and Their Graphs:
Solving Problems Involving Direct Variation
PUNCHLINE 0 Algebra o Book A
@2006 Marcy Mathworks
7,10