Answer:
x=3.4
y=-6.75
Step-by-step explanation:
5x+4y=-10 (equation 1 )
-5x+3y=-17 (equation 2)
7y=-27
y=-6.75
substitution (equation 1 ) y=-6.75
5x-27=-10
5x=17
x=3.4
Amy(A): D + 12
Doug(D):D
Ginger(G):2D
SumOfAll(S)=208 : Total points / sum of all three friends
(D+12)+D+2D=208
D+12+3D=208 - transpose 12 to the right side
4D=208-12
4D = 196 - divide both sides by 4
D=49
Therefore, Doug scored 49
Use the midpoint formula.
(x1+x2)/2 , (y1+y2)/2
Then you should be able to find the reflection line based on where the middle of the two points are.