Question

Quadratic functions can be used to describe the rate at which an object will fall and predict when it will land or how high it may
go. Create a quadratic function using the function y = - 16tto help predict when an object will return to the ground from
being kicked, dropped, or thrown. In 3 in a 7th graders response sentences, describe the scenario in which you will use the function. Write the complete function and explain the meaning of the variable t and the constant value.

Answer 1

I'm standing on a 5-foot porch and I throw a ball straight up at 20 ft/s, and I want to use a quadratic to predict how high it goes and when it will land. The complete function for the ball's height y (in feet) after t seconds is y = -16t^2 + 20t + 5. Here t is the time in seconds, -16 comes from gravity (it makes the ball slow down and fall, measured in feet per second squared), 20 is the ball's initial upward speed in ft/s, and 5 is the starting height in feet (to find when it lands set y = 0 and solve for t).