Answer:
The length is 14 units
Step-by-step explanation:
Take the value at point F and subtract the value at point E
F = 19
E = 5
19 -5 =14
The length is 14 units
If the line is linear, a straight line, both should get the same answer. All the points on the line have the same ratio. So when they both solve for the slope, they will get the same answer.
The slope (or average rate of change) formula is:

. It is easy to remember as "slope is easy and fun, rise over run" where the y-values of the 2 points would be the "rise" and the x-values of the 2 points would be the "run" So with two points, you label one point as

and the other as

. Then you insert these points into the slope formula (m represents slope). So,

where (-3,6) is x2 and y2 and (5,1) is x1 and y1. It would simplify to

.
Answer:
a) The maximum height is approx 15.5 unit.
b) The time it will take for Joey to reach the water is 1.45 hour.
Step-by-step explanation:
Given : When Joey dives off a diving board, the equation of his pathway can be modeled by 
To find : a) Find Joey's maximum height.
b) Find the time it will take for Joey to reach the water.
Solution :
Modeled
....(1)
a) To find maximum height
Derivate (1) w.r.t. t,

For critical point put h'=0,



Derivate again w.r.t. t,

It is maximum at t=0.46875.
Substitute t in equation (1),



The maximum height is approx 15.5 unit.
b) To find the time it will take for Joey to reach the water.
Put h=0 in equation (1),
Apply quadratic formula, 
Here, a=-16 , b=15, c=12
Reject negative value.
The time is t=1.45.
The time it will take for Joey to reach the water is 1.45 hour.