9.2 x 13.8 = 126.96, now usually to get the area of a triangle we would half this but because we have two of the same triangle we would then have to double it again so they cancel each other out. We then do 6.9 x 9.2 which equals 63.48 and again we have two of the same triangle so no need to half it. So we add the two totals of 126.96 and 63.48 together to get 190.44.
Let the distance of the first part of the race be x, and that of the second part, 15 - x, then
x/8 + (15 - x)/20 = 1.125
5x + 2(15 - x) = 40 x 1.125
5x + 30 - 2x = 45
3x = 45 - 30 = 15
x = 15/3 = 5
Therefore, the distance of the first part of the race is 5 miles and the time is 5/8 = 0.625 hours or 37.5 minutes
The distance of the second part of the race is 15 - 5 = 10 miles and the time is 1.125 - 0.625 = 0.5 hours or 30 minutes.
Answer:
Step-by-step explanation:
The equation that models the height of the ball in feet as a function of time is

Where
is the initial height,
is the initial velocity and t is the time in seconds.
We know that the initial height is:
The initial speed is:

So the equation is:

The ball hits the ground when when
So

We use the quadratic formula to solve the equation for t
For a quadratic equation of the form

The quadratic formula is:

In this case

Therefore

We take the positive solution.
Finally the ball takes 2.47 seconds to touch the ground