At the start of a basketball game, the referee tosses a ball into the air for the jump ball. The equation that models the height of the ball is h(t) = -16t2 + 30t + 8. During what time interval is the height of the ball above 10 feet? (Round your answer to the nearest tenth of a second.)
a)
Between 1.1 and 1.6 seconds
b)
Between 0.3 and 2.1 seconds
c)
Between 0.1 and 1.8 seconds

Question

At the start of a basketball game, the referee tosses a ball into the air for the jump ball. The equation that models the height of the ball is h(t) = -16t2 + 30t + 8. During what time interval is the height of the ball above 10 feet? (Round your answer to the nearest tenth of a second.)
	a)	
Between 1.1 and 1.6 seconds
	b)	
Between 0.3 and 2.1 seconds
	c)	
Between 0.1 and 1.8 seconds

anonymous · Answer

Solve $h(t) > 10$, let the solutions be $t_1$ and $t_2$, then you are looking for $|t_1-t_2|$.