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A rocket is launched from a tower. The height of the rocket, y in feet, is related to the time after launch, x in seconds, by the given equation. Using this equation, find the time that the rocket will hit the ground. y=-16x^2+266x+102 The amount of time it takes for the rocket to hit the ground is ____ seconds

User Blacklight
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1 Answer

2 votes

Answer:

17 seconds

Explanation:

Solution:-

The trajectory of a rocket launched is modeled by a parabolic path via a quadratic equation as follows:


y = -16x^2 + 266x +102

Where,

y: The height of the rocket from ground

x: The time taken since rocket launch

We are to determine the time ( x ) it takes for the rocket to hit the ground. This can be determined by setting the quantity ( y ) to zero as follows


y = -16x^2 + 266x +102 = 0\\\\ -16x^2 + 266x +102 = 0

solve the quadratic equation using quadratic formula as follows:


x = (-b +/- โˆš(b^2 - 4ac) )/(2a) \\\\x = (-266 +/- โˆš(266^2 - 4*(-16)*(102)) )/(2*(-16)) \\\\x = (-266 +/- 278 )/(-32) \\\\x = 8.3125 +/- 8.6875\\\\x = 17 , -0.375

Answer: Ignore the negative value for time " -0.375 ". Hence, the rocket hits the ground at time t = 17 seconds

User Franziska
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