Question

5/x+y -2/x-y 15/x+y +7/x-y

Answer 1

$\frac{5}{x+y}-\frac{2}{x-y}\times\frac{15}{x+y}+\frac{7}{x-y}\\ =\frac{5}{x+y}-\frac-{30}{{x}^{2}-{y}^{2}}+\frac{7}{x-y}\\= \frac{5(x-y)+7(x+y)}{{x}^{2}-{y}^{2}}-\frac{30}{{x}^{2}-{y}^{2}}\\=\frac{12x-2y+30}{{x}^{2}-{y}^{2}}$