So,
We'll just use A to represent both Jan and Mya's miles, since they ran the same number.
We have the equations:
1. Jan (J) = Mya (M)
2. Sara (S) = M - 8
3. 2A + S = 64
J = M
S = M - 8
We'll just use A to represent both J and M.
S = M - 8
We'll use Elimination by Substitution.
2A + A - 8 = 64
Collect Like Terms
3A - 8 = 64
Add 8 to both sides
3A = 72
Divide both sides by 3
A = 24
Since
A = J
and
A = M
and
J = M
then
J = 24
M = 24
Substitute
S = 24 - 8
S = 16
Check
24 + 24 + 16 = 64
64 = 64 This checks.
So,
J = 24
M = 24
S = 16
Answer:
8
Step-by-step explanation:

I think the answer is both x and y are positive
Yes. That's exactly right. Good work.
7 unit to the left, means it is 7 less than -1.
-1-7 = -8
Ans: -8