а) \(\frac{(y-4)(y+4)}{3(y+4)} = \frac{y-4}{3}\); в) \(\frac{(c+2)^2}{7c(c+2)} = \frac{c+2}{7c}\); д) \(\frac{(a+5)^2}{(a-5)(a+5)} = \frac{a+5}{a-5}\); б) \(\frac{5(x-3y)}{(x-3y)(x+3y)} = \frac{5}{x+3y}\); г) \(\frac{6c(d - 3)}{(d-3)^2} = \frac{6c}{d-3}\); е) \(\frac{(u-3)(u+3)}{5(y+3)}\)