Question

A hovercraft takes off from a platform. Its height (in meters), xxx seconds after takeoff, is modeled by: h(x)=-2x^2+20x+48h(x)=−2x 2 +20x+48h, left parenthesis, x, right parenthesis, equals, minus, 2, x, start superscript, 2, end superscript, plus, 20, x, plus, 48 How many seconds after takeoff will the hovercraft reach its maximum height?

Answer 1

Answer:

Step-by-step explanation:

Given A hovercraft takes off from a platform. Its height (in meters), xxx seconds after takeoff, is modeled by: h(x) = -2x^2+20x+48. How many seconds after takeoff will the hovercraft reach its maximum height.

We have the equation - 2x^2 + 20 x + 48

Since we need to find the coordinates vertex ,

x = - b/2a

x = -(20)/2(2)

x = - 20/4

x = - 5 secs

Now the hovercraft after 5 secs of takeoff reaches the maximum height

Now substitute x = 5 in the given  equation.

So - 2(5)^2 + 20(5) + 48

148 - 50

= 98 mtrs

So maximum height will be 98 mtrs.

Answer 2

Answer:

33 meters

Step-by-step explanation:

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