Question

H=-16t^2+46t+6 after how many seconds will the ball hit the ground?

Answer 1

ball hit the ground is when the function equals zero
0=-16t^2+46t+6
we can't factor so use quadraticformula

for
ax^2+bx+c=0
x=
`(-b+/- √(b^2-4ac) )/(2a)`
x=
`(-46+/- √(46^2-4(-16)(6)) )/(2(-16))`
x=
`(-46+/- √(2116+384) )/(-32)`
x=
`(-46+/- √(2500) )/(-32)`
x=
`(-46+/- 50 )/(-32)`
x=
`(-46+ 50 )/(-32)` or
`(-46- 50 )/(-32)`
x=
`(4)/(-32)` or x=
`(-96)/(-32)`
x=-1/6 or x=3

we cannot have negative time because time starts at 0
disregard -1/6 as a possible answer


answer is after 3 seconds