Question

ALG 2


A football is kicked into the air from an initial height of 3 feet. The height, in feet, of the football above the ground is given by s(t) - -16t^2+35t + 3 , where t is time in seconds and>0 . Which is closest to the time when the football will be 20 feet above the ground?

Answer 1

2.72 seconds
0.73 seconds or 1.46 seconds
0.53 seconds
0.53 seconds or 2.72 seconds

Answer 2

here we have to solve this equation:
\[\huge - 16{t^2} + 35t + 3 = 20\]

Answer 3

after a simplification, we get:
\[\huge 16{t^2} - 35t + 17 = 0\]
next, please apply the standard formula:
\[\huge t = \frac{{ - b \pm \sqrt {{b^2} - 4ac} }}{{2a}}\]