A baseball is thrown into the air from the top of a 224-foot tall building. The baseball's approximate height over time can be represented by the quadratic equation h(t) = -16t2 + 80t + 224, where t represents the time in seconds that the baseball has been in the air and h(t) represents the baseball's height in feet. When factored, this equation is h(t) = -16(t - 7)(t + 2). What is a reasonable time for it to take the baseball to land on the ground?

A.
5 seconds
B.
9 seconds
C.
2 seconds
D.
7 seconds

D. 7s

Step-by-step explanation:

h(t) = height off the ground

We know the height of the ball at the point when it hits the ground will be 0, so we set h(t) = 0:

h(t) = -16(t - 7)(t + 2) = 0

In order for this to be true, either:

"t - 7 = 0" or "t + 2 = 0"

We can solve these to get the times at which the ball will hit the ground, which gives:

t = 7 or t = -2

-2s is not a logical time because the ball can't hit the ground before it is thrown so this solution is not relevant;

7s therefore is the correct solution

step-by-step explanation:

given that there are two triangles j'k'l' and jkl>

the former is got by dilating the second one.

when drawn on a grid, (graph paper) coordinates of vertices of first triangle is

(6,12)j, (9,6)k and (12,9)l

side jk has length = distance between j and k

=

side j'k'=distance between j' and k'

=

ie j'k'l' has sides 1/3 of that of corresponding sides of jkl.

hence scale factor of 1/3 is used to get j'k'l'from jkl

1. sometimes

2. never true

3. sometimes

step-by-step explanation:

these are pretty self explanatory if you know what supp right and com angles are