Помогите пожалуйста

1a)

$=\cfrac{3c-a-a+7c}{4c}=\cfrac{10c-2a}{4c}=\cfrac{5c-a}{2c}$

1б)

$=\cfrac{2p+(3-p)}{p+3}=\cfrac{p+3}{p+3}=1$

1в)

$=\cfrac{x^2}{x-4}-\cfrac{4x}{x-4}=\cfrac{x\cdot (x-4)}{x-4}=x$

1г)

$=\cfrac{m-n}{m^2-n^2}=\cfrac{m-n}{(m-n)\cdot (m+n)} = \cfrac{1}{m+n}$

2)

$=\cfrac{60+y+15y+4+y^2}{(y+8)^2}=\cfrac{y^2+16y+64}{(y+8)\cdot(y+8)}=\cfrac{y^2+16y+64}{y^2+8y+8y+64}= \\ =\cfrac{y^2+16y+64}{y^2+16y+64}=1$