When a 49 pound weight is attached to a spring, the spring stretches 7 inches. Assume that the length of the spring y varies directly withthe

"When a 49 pound weight is attached to a spring, the spring stretches 7 inches. Assume that the length of the spring y varies directly withthe weight attached x. Write and solve a direct variation equation to find the length of the spring when a 63 pound weight is attached"

 

Direct variation means:   y = k*x   where k is a constant

 

Find k by using the given values of y = 7 inches and x = 49 pounds:     7 = k*49   so k = 1/7 inches per pound

 

Now, when x = 63 pounds we have:   y = (1/7)*63 inches or y = 9 inches

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