A rock is launched from a cannon. After 1 second, the rock is 243 feet in the air; after 2 seconds, it is 452 feet in the air. Using the quadratic function, find the height, in feet, of the rock after 5 seconds in the air

Respuesta :

The height would be 513.20ft of the ticket after 7 seconds in the air.
y = ax^2 + bx
243 = a + b . . . (1)
452 = 4a + 2b
226 = 2a + b . . . (2)

(2) - (1) => a = -17
From (1), b = 243 + 17 = 260

y = -17x^2 + 260x

After 5 seconds, y = -17(5)^2 + 260(5) = -425 + 1300 = 875 feet.