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The function h(t)=-16t2+32t+128 represents the height of a cnnoj ball in feet t seconds after it is shot from a cannon. How many seconds does it take the cannonball to hot its target on thr grownd

User Flauwekeul
by
8.5k points

1 Answer

5 votes

Answer:

4 seconds

Explanation:

To solve this problem you will use the quadratic formula:
(-b\pm√(b^2-4ac) )/(2a).

Identify the a, b, and c values of the given quadratic equation:

  • a = -16
  • b = 32
  • c = 128

Substitute these values into the quadratic formula.


(-(32)\pm√((32)^2-4(-16)(128)) )/(2(-16)) \rightarrow (-32\pm√((1024)+(8192)) )/(-32) \rightarrow (-32\pm√(9216) )/(-32) \rightarrow (-32\pm96)/(-32)

Now split this into two equations.


(-32+96)/(-32) ~and~(-32-96)/(-32)

Positive case:
(-32+96)/(-32) \rightarrow (64)/(-32) =-2

Negative case:
(-32-96)/(-32) \rightarrow (-128)/(-32) =4

Since time cannot be negative, the cannonball takes 4 seconds to hit its target on the ground.

User Choz
by
7.6k points
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