Answer:
part 1) 0.78 seconds
part 2) 1.74 seconds
Step-by-step explanation:
step 1
At about what time did the ball reach the maximum?
Let
h ----> the height of a ball in feet
t ---> the time in seconds
we have

This is a vertical parabola open downward (the leading coefficient is negative)
The vertex represent a maximum
so
The x-coordinate of the vertex represent the time when the ball reach the maximum
Find the vertex
Convert the equation in vertex form
Factor -16

Complete the square


Rewrite as perfect squares

The vertex is the point 
therefore
The time when the ball reach the maximum is 25/32 sec or 0.78 sec
step 2
At about what time did the ball reach the minimum?
we know that
The ball reach the minimum when the the ball reach the ground (h=0)
For h=0



square root both sides


the positive value is

Answer:
6.75
Step-by-step explanation:
h=hat, s=scarf
5h + 1s = $47 (equation 1)
2h + 2s = $40 (equation 2)
multiply equation 1 by 2 , we get: 10h + 2s = $94 (equation 3)
equation 3 minus equation 2, we get:
8h = $54 ⇒ h = $6.75 ⇔ 1 hat cost $6.75
substitute h = $6.75 into equation 2 to find s,
2($6.75) + 2s = $40
$13.5 + 2s = $40
2s = $26.5
s = $13.25 ⇔ 1 scarf cost $13.25
Car load and insurance premium
Answer: 3:35
Step-by-step explanation:
Answer:
y = 500x + 1000
Step-by-step explanation:
The standadrd equation of a line is expressed as y = mx+b
m is the slope
is the y-intercept
Using the coordinate points (0, 1000) and (6, 4000)
Slope = y2-y1/x2-x1
Slope = 4000 - 1000/6-0
Slope m = 3000/6
Slope m = 500
Since the line cut the y axis at y = 1000, hence the intercept b = 1000
Get the required equation;
Reall that y = mx+b
y = 500x + 1000