Page 128 - Senior Math

The values of x and y vary directly. Write an equation that relates the variables. 1) 𝑥=2,𝑦=5 2) 𝑥=−4,𝑦=6
3) 𝑥=−5,𝑦=10 4) 𝑥=12,𝑦=3 The values of x and y vary inversely. Write an equation that relates the variables.
9)
5) 𝑥=2,𝑦=5 6) 𝑥=−4,𝑦=6 7) 𝑥=−5,𝑦=10 8) 𝑥=12,𝑦=3
The speed of the water in a whirlpool varies inversely with the radius. The water speed is 2.5 feet per second at a radius of 30 feet.
a) Write a linear model that relates speed and radius.
b) What is the speed of the water at a radius of three feet?
10) The number of calories a person burns and the time the person spends performing an activity vary directly. A 150 pound person burns 75 calories by sitting in class 50 minutes.
a) Write a linear model that relates calories and time.
b) How long would this person need to sit in class to burn 545 calories?
11) When a seesaw is balanced, each person’s weight varies inversely with the distance from center support. A person who weighs 90 pounds sits at one end of a 12 foot seesaw
a) Write a linear model that relates weight and distance.
b) How far from the support must a 120 pound person sit to balance the seesaw?
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