solve:

y-3/y-7 - y+1/y+7 + y-63/y2-49

2 answers

since y^2-49 = (y-7)(y+7), use that as a common denominator. The numerators then satisfy

(y-3)(y+7) - (y+1)(y-7) + (y-63)
y^2 + 4y - 21 - y^2 + 6y + 7 + y - 63
11y - 77
11(y-7)

So, the final fraction is

11(y-7)/(y^2-49)
hey! That's just 11/(y+7)