When the firecracker hits the ground, H(t) = 0.0 = -16t^2 + 90t + 160 Using the quadratic formula,t = (-90 +- sqrt(90^2 - 4(-16)(160))) / 2(-16)t = -1.42 ort = 7.04
The negative time is extraneous. Therefore,t = 7.04 s.
Seven Seconds is your answer!
Answer:
A, y = 3x/2 - 12
Step-by-step explanation:
Use the equation y = mx + b.
m = 3/2
b = -12
y = 3x/2 - 12
-18-(-12)=-6
Since there is two negative sign, it turns into positive meaning the -12 becomes positive 12 and the -18 stays same. So -18+12=-6 because 18 is bigger than 12 and it's negative so the final answer should be negative.
Hint: when you see two negative sign just turn them into plus sign.