Answer:
after 21 seconds
Step-by-step explanation:
Given
h = - 16t² + 272t + 1344
When the ball strikes the ground then h = 0, that is
- 16t² + 272t + 1344 = 0 ( divide through by - 16 )
t² - 17t - 84 = 0 ← in standard form
(t - 21)(t + 4) = 0 ← in factored form
Equate each factor to zero and solve for t
t - 21 = 0 ⇒ t = 21
t + 4 = 0 ⇒ t = - 4
However t > 0 thus t = 21
The ball strikes the ground after 21 seconds.
Answer:
- 41
- -5
- 42
- 21
- 4
- 7
Step-by-step explanation:
C. 8.64m^2 because one face of the cube has a surface area of 1.44m^2 (1.2*1.2) and a cube has 6 sides (6*1.44).
Answer:
jen
Step-by-step explanation:
Jordan's total number of sit-ups
20+24+28+32= 104
Jen's total number of sit-ups
40+48+56+62=208
divide Jen's sit-ups by Jordan's sit-ups
208/104=2