word problem with velocity and quadratic fomula

[Single69%]

h= 16t^2-32t+320 shows the height of a ball thrown downward from a building 320 feet in height. the initial velocity of the ball is 32 feet per sec downward. How many seconds would it take that ball to reach 48 feet

 

[Quaid]

h = -16t^2 - 32t + 320 shows the height of a ball thrown downward from a building 320 feet in height

How many seconds would it take that ball to reach 48 feet

Either you forgot to type a negative sign, or they did (added in red above).

Where are you stuck?

They're asking you to solve for t, when h = 48.

Have you solved quadratic equations before?

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