Hello : let h =f(t)
<span>the ball hit the ground if : f(t) =0
solve : </span><span> -16t² + 20t + 6=0
</span><span>Δ = b²-4ac ... a = -16 b= 20 c =6
</span>Δ =(20)²-4(-16)(6) = 784 = 28²
t1 = (-20-28)/-32 = 48/32 =3/2
t2 =(-20+28) /-32 <span>< 0 refused
conclusion : t=3/2</span>
There is 18% of decrease in the price of gasoline
I believe the answer is 5 • (f - 32)<span> / 9 </span>
1. Distance between points is 7
2. Distance between points is 6
3. Distance between points is 10
4. Distance between points is 6
5. Distance between points is 4