Please help with this

Question

A batter hits a fly ball. A scout in the stands makes the following observations.

 

Time(seconds).75, 1.5, 2, 2.75, 3.25, 4.75

Height(feet) 77, 133, 160, 187, 194, 169

 

The function is Quadratic
The best-fit equation is Y=-15.90x^2+ 110.48x +3.02

Determine the initial velocity of the baseball and the height of the ball when hit. Round to the nearest hundredth.

 

Answer 1

1. When the ball is hit, x = 0.  So to find the height at that time, just put in 0 for x in the equation.  x² and x terms both become 0, and all that's left is 3.02.  So the initial height is 3.02 feet.

 

2. In a quadratic model for the motion of an object influenced by gravity, the coefficient of the x term is the initial velocity.  So that is 110.48 feet per second.