A diver dives from the board at a local swimming pool. Her height, y, in metres, above the water in terms of her horizontal distance, x, in metres, from the end of the board is given by y= -x^2 + 2x + 3. What is the diver's maximum height?

Respuesta :

Answer:

4 meters

Step-by-step explanation:

Given a quadratic equation in which the coefficient of [tex]x^2[/tex] is negative, the parabola opens up and has a maximum point. This maximum point occurs at the line of symmetry.

Since the divers height, y is modeled by the equation

[tex]y= -x^2 + 2x + 3[/tex]

Step 1: Determine the equation of symmetry

In the equation above, a=-1, b=2, c=3

Equation of symmetry, [tex]x=-\dfrac{b}{2a}[/tex]

[tex]x=-\dfrac{2}{2*-1}\\x=1[/tex]

Step 2: Find the value of y at the point of symmetry

That is, we substitute x obtained above into the y and solve.

[tex]y(1)= -1^2 + 2(1) + 3=-1+2+3=4m[/tex]

The maximum height of the diver is therefore 4 meters.