Question

Can someone help?
A model rocket is launched from a roof into a large field. The path of the rocket can be modeled by the equation
y = –0.04x2 + 8.3x + 4.3 , where x is the horizontal distance, in meters, from the starting point on the roof and y is the height, in meters, of the rocket above the ground. How far horizontally from its starting point will the rocket land? Round your answer to the nearest hundredth meter

THaks

Answer 1

this is what i am thinking.....
if you want to find how far horizontally from the roof the rocket would travel, then the height (y) above the ground has to be zero. so your equation now becomes
0=-0.04x^2 + 8.83x +4.3
to find x, you can use the quadratic formula,
\[x = \frac{ -b \pm \sqrt{b ^{2}-4ac} }{ 2a }\]
you would get two values for x one is positive and the other is negative. Since distance travelled can never be negative, your answer would be the positive value of x.