(d+2)^2/7d(d+2)=(d+2)/7d
3(x-y)^2/6(x-y)(x+y)=(x-y)/2(x+y)
1)(d+2)^2/7d(d+2)=(d+2)/7d
2)3(x-y)^2/6(x-y)(x+y)=(x-y)/2(x+y)
как-то так)))
