Answer:
U, V
Step-by-step explanation:
Kinetic Energy
=
1
2
m
v
2
=
1
2
1120
⋅
40
2
=
896000
J
=
8.96
⋅
10
5
J
Nancy's rate=27 mph
Greg's rate=45 mph
t=Greg's time
t+2=Nancy's time
Since they both traveled same distance then:
27(t+2)=45t
27t+54=45t
18t=54
t=3 hours
Greg will pass Nancy after 3 hours
I think it’s 25 and two half’s
So we have the system of equations:

equation (1)

equation (2)
To use substitution, we are going to solve for one variable in one of our equations, and then we are going to replace that value in the other equation:
Solving for

in equation (2):



equation (3)
Replacing equation (3) in equation (1):






equation (4)
Replacing equation (4) in equation (3):



We can conclude that the solution of our system of equations is <span>
(7/5, 21/10)</span>