Some fireworks are fired vertically into the air from the ground at an initial speed of 80 feet per second. The equation for this object's height (h) at the time (t) seconds after launch is h(t)=-16t^2 + 80t. Find the domain of the function.

77

step-by-step explanation:

we have three similar triangles, because each has a right angle and shares an angle.   let's write the angles in order: opposite to short leg, long leg, hypotenuse.

cab similar to bad similar to cbd

or as ratios,

ca: ab: cb = ba: ad: bd = cb: bd: cd

we also know

ac = ad + cd

(ad+cd): ab: cb = ba: ad: bd = cb: bd: cd

(ad+cd)/cb=cb/cd

we have cb=6, ad=5 and seek x=cd.

we reject the negative root and conclude x=4

answer: 4

21

jk it's 20

step-by-step explanation: