Urgent Questions

5. If the distance between (x,15) and (7,9) is equal to the distance between (x+9,0) and (-2,0), find the value of x.
(7-x)^2+(9-15)^2=(-2-x-9)^2
x^2-14x+49+36=x^2+22x+121
36x=-36
x=-1
6. Four points A(5,-1), B(-3,9), C(y - 4,4) and D(-5,2y) are given. If AB//CD, find the value of y.
AB//CD
slope are equal
(-1-9)/(5+3)=(4-2y)/(y-4+5)
-10/8=(4-2y)/(y+1)
-10y-10=32-16y
6y=42
y=7