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, to the nearest 10oth of second.y=−16x2+89x+50
Q. 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, to the nearest 10oth of second.y=−16x2+89x+50
Find x when y=0: First, we need to find when y=0, because that's when the rocket hits the ground.So we set the equation to 0 and solve for x: 0=−16x2+89x+50.
Use quadratic formula: Now we need to use the quadratic formula to solve for x, which is x=2a−b±b2−4ac. Here, a=−16, b=89, and c=50.
Calculate discriminant: Let's calculate the discriminant first: b2−4ac=892−4(−16)(50). That's 7921+3200, which equals 11121.
Take square root: Now we take the square root of the discriminant: 11121=105.455.
Plug values into formula: We can now plug the values into the quadratic formula: x=2⋅−16−89±105.455.
Calculate first solution: We have two possible solutions for x: x=−32−89+105.455 and x=−32−89−105.455.
Calculate second solution: Calculating the first solution: x=(16.455)/−32=−0.514. This doesn't make sense because time can't be negative.
Round to nearest hundredth: Calculating the second solution: x=(−194.455)/−32=6.076. This is the time when the rocket will hit the ground.
Round to nearest hundredth: Calculating the second solution: x=(−194.455)/−32=6.076. This is the time when the rocket will hit the ground.Finally, we round the time to the nearest hundredth of a second: 6.08 seconds.
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