The quadratic function d = –2x^2 + 15 models a skateboarder’s distance, in feet, from the bottom of a hill x seconds after the skateboarder starts moving down the hill. After how many seconds is the skateboarder 8 ft from the bottom of the hill?

4

step-by-step explanation:

the answer is (-8,-5)

step-by-step explanation:

the endpoint to midpoint is half the length. the length is (-2,-1) so when you are at the midpoint just add it to it to find your answer -6+(-2)= -8 and -4+(-1)=-5 so (-8,-5)