Answer:
0.18 sec or 3.4 sec.
For second part, it will take 3.7 sec.
First part:
Set h(t) = 17and solve for t.
-16t²+ 58t + 7= 17
-16t² + 58t - 10 = 0
Solve this quadratic equation for t. You should get 2 positive solutions. The lower value is the time to reach 17 on the way up, and the higher value is the time to reach 17 again, on the way down.
Second part:
Set h(t) = 0 and solve the resulting quadratic equation for t. You should get a negative solution (which you can discard), and a positive solution. The latter is your answer.
Answer:
Step-by-step explanation:
1) ΔCPD & ΔEPF
∠CPD = ∠EPF { Vertically opposite angles}
∠CDP = ∠PFE {CD║EF, FD is transversal, Alternate interior angles are equal}
ΔCPD ≈ΔEPF {AA criteria for similarity }
Cross multiply
EF * 15 = 27 * 7.5
EF = 27 * 0.5
EF = 13.5 cm
ii) EF // AB, so Triangles ACB & ECF are similar triangles
AC = 37.5 cm