Ming throws a stone off a bridge into a river below.

The stone's height (in meters above the water), 3 seconds after Ming threw it, is modeled by:

h(x) = -5(x - 1)2 + 45

How many seconds after being thrown will the stone reach its maximum height?

Please help!

In 1 seconds after being thrown will the stone reach its maximum height.

Step-by-step explanation:

Given : Ming throws a stone off a bridge into a river below.  The stone's height (in meters above the water), 3 seconds after Ming threw it, is modeled by : .

To find : How many seconds after being thrown will the stone reach its maximum height?

Solution :

The maximum height is attain by getting the vertex of the model.

The vertex form of the quadratic equation or parabola is

Where, (h,k) are the vertex.

On comparing with the given model,

a=-5, h=1 and k=45

The vertex of the equation is (h,k)=(1,45).

Now the maximum height is 45 m and number of second is 1 sec.

Therefore, In 1 seconds after being thrown will the stone reach its maximum height.

answer: x=3 and y=4

step-by-step explanation:

x = 12

y = 1

for the points!