Question

A ball is launched from a sling shot. After 1 second, the ball is 121 feet in the air. After 2 seconds, it's 224 feet in the air. Using quadratic functions, find the height, in feet, of the ball after 3 seconds in the air.

Answer 1

you getting any luck with these yet :)

Answer 2

0a +0b +c = 0 ; c = 0
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a + b = 121 ; a = 121-b
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4a +2b = 224
4(121-b) + 2b = 224
484 -4b +2b = 224
484 - 224 = 2b
260/2 = b ; b = 130
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a + 130 = 121
a = 121 - 130 ; a = -9
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our quadratic formula becomes:

y = -9x^2 +130x

y = -9(3)^2+130(3)
y = -81 + 390

y = 309 ; the height is 309 ft after 3 seconds.

Answer 3

typo..... our quadratic EXPRESSION becomes.. lol, my fauxpas