Arock is thrown and follows the curve given by the equation d = -t2 + 4t + 5, where d is the distance in feet and t is the time in seconds. when will the rock hit the ground? 9 seconds 5 seconds 2 seconds 1 second

5 seconds

Step-by-step explanation:

The relationship between "d" and "the ground" is not described. If we assume that "d" is distance above the ground, then the rock will hit the ground when d=0. This gives rise to the quadratic equation ...

-t^2 +4t +5 = 0

-(t -5)(t +1) = 0

t = 5 or t = -1 are solutions. Only the positive solution is useful.

The rock will hit the ground after 5 seconds.

hey there!

12 is twice as much as 6 because 6 goes into 12 2 times.

since the rabbit is twice as tall, we should multiply the weight of the first rabbit, 0.25, by 2.

0.25 x 2 = 0.5

therefore, the 12 inch chocolate rabbit weighs 0.5 lb, or half a pound.

hope this !