Решите пожалуйста (заранее спасибо)❤❤

1) $\frac{c+d}{2a} + \frac{2c-d}{2a} = \frac{3c}{2a}$
2) $\frac{10-b}{ a^{3} } + \frac{3a-b}{ a^{3} } = \frac{10-b-3a+b}{ a^{3} } = \frac{10-3a}{ a^{3} }$
3) $\frac{y}{n-2} + \frac{c}{2-n} = \frac{y}{n-2} - \frac{c}{n-2} = \frac{y-c}{n-2}$
4) $\frac{3x+7y}{4} - \frac{y-3x}{4} = \frac{3x+7y-y+3x}{4} = \frac{6y+6x}{4} = \frac{3y+3x}{2}$
5) $\frac{12n-m}{27m} + \frac{m+15n}{27m} = \frac{12n-m+m+15n}{27m}= \frac{27n}{27m} = \frac{n}{m}$
6) $\frac{ a^{2} }{a-3} - \frac{9}{a-3} = \frac{ a^{2} -9}{a-3} = \frac{(a-3)(a+3)}{a-3} = a+3$
7) $\frac{5x}{x-y} + \frac{5y}{y-x} = \frac{5x}{x-y} - \frac{5y}{x-y} = \frac{5x-5y}{x-y} = \frac{5(x-y)}{x-y} = 5$
8) $\frac{3a-2b}{a-3b} - \frac{5b-4a}{3b-a} = \frac{3a-2b}{a-3b} + \frac{5b-4a}{a-3b} = \frac{3a-2b+5b-4a}{a-3b} = \frac{3b-a}{a-3b} = \frac{-(a-3b)}{a-3b} = -1$