Sandra throws an object straight up into the air with an initial velocity of 38 ft/s from a platform that is 30 ft above the ground. use the formula h(t)=−16t2+v0t+h0 , where v0 is the initial velocity and h0 is the initial height. how long will it take for the object to hit the ground?
a. 1 s

b. 2 s

c. 3 s

d. 4 s

The answer is C.

Step-by-step explanation:

Given formula h(t)=−16t2+v0t+h0 , where v0 is the initial velocity and h0 is the initial height.

In this case, the initial postion is a platform 30ft above ground so h0=+30

The initial velocity is 38 ft/s straight up into the air so v0=+38

h(t)=-16t2+38t+30

When the object hits the ground, h=0.

h=-16t2+38t+30=0

Simplifying 8t2-19t-15=0

(8t+5)(t-3)=0

t=-5/8 or 3

As time cannot be -ve, t=3s. The answer is C.

(w – 2.5)(w + 2.5)

(–4v – 9)(–4v + 9)

step-by-step explanation:

you can first factor out the n to get n(1+5). we know that 1+5 is 6, so we just have 6n.