-35+5r=4(r-7)
Multiply the bracket by 4
(4)(r)(4)(-7)
4r-28
-35+5r=4r-28
Move 4r to the other side. Sign changes from +4r to -4r.
-35+5r-4r=4r-4r-28
-35+5r-4r=-28
-35+r=-28
Move -35 to the other side. Sign changes from -35 to -35.
-35+35+r=-28+35
r=7
Answer: r=7