a physics student stands at the top of hill that has an elevation of 37 meters. he throws a rock and it goes up into the air and then falls back past him and lands on the ground below. the path of the rock can be modeled by the equation y=-0.02x^2+0.8x+37 where x is the horizontal distance in the meters from the starting point on the top of the hill and y is the heigth in meters, of the rock above the ground. how far horizontally from its starting point will the rock land? round your answer to the nearest hundredth?

37.00m
67.43m
27.43m
37.78m

Question

a physics student stands at the top of hill that has an elevation of 37 meters. he throws a rock and it goes up into the air and then falls back past him and lands on the ground below. the path of the rock can be modeled by the equation y=-0.02x^2+0.8x+37  where x is the horizontal distance in the meters from the starting point on the top of the hill and y is the heigth in meters, of the rock above the ground. how far horizontally from its starting point will the rock land? round your answer to the nearest hundredth?

37.00m
67.43m
27.43m
37.78m

anonymous · Answer

@robtobey please help

jdoe0001 · Answer

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notice, it's just a quadratic equation, the rock will land when "y = 0"
so just set y = 0, and solve for "x", like you'd any quadratic equation