1) A projectile is thrown upward so that its distance above the ground after t seconds is
h=-10t2 +440 t. After how many seconds does it reach its maximum height?​

Respuesta :

Answer:

After 22 seconds the projectile reach its maximum height of 4,840 units

Step-by-step explanation:

we have

[tex]h(t)=-10t^{2}+440t[/tex]

This is a vertical parabola downward (because the leading coefficient is negative)

The vertex is a maximum

Find out the coordinates of the vertex

Convert the quadratic equation in vertex form

Factor -10

[tex]h(t)=-10(t^{2}-44t)[/tex]

Complete the square

[tex]h(t)=-10(t^{2}-44t+22^2)+(10)(22^2)[/tex]

[tex]h(t)=-10(t^{2}-44t+22^2)+4,840[/tex]

Rewrite as perfect squares

[tex]h(t)=-10(t-22)^{2}+4,840[/tex]

The vertex is the point (22,4,840)

therefore

After 22 seconds the projectile reach its maximum height of 4,840 units