Antoine stands on a balcony and throws a ball to his dog, who is at ground level. the ball's height (in meters above the ground), x xx seconds after antoine threw it, is modeled by: h ( x ) = − 2 x 2 + 4 x + 1 6 h(x)=−2x 2 +4x+16h, left parenthesis, x, right parenthesis, equals, minus, 2, x, start superscript, 2, end superscript, plus, 4, x, plus, 16 how many seconds after being thrown will the ball hit the ground?

there is no question content here, but you for the free points! : d

- "runner b is moving at a slower rate."

- "the graphs shown are graphs of distance(km) against time(min).

the slopes of this graphs are are given by:

slope = (change in y)/(change in x)

= (change in distance)/(change in time)

this is the formula for finding the speed. so, the slope of these graphs represent the speed of the runner.

taking each division in the graph to represent 1 on both axis:

runner a ⇒ speed = (2-0)/(1-0)

= 2/1

= 2 km/min

runner b ⇒ speed = (3-0)/(3-0)

= 3/3

= 1 km/min

this shows that   runner b is moving at a slower rate."