Question

Сократите дробь:
у^2-9х^2
18х^26ху

Answer 1

$\frac{ y^{2}-9 x^{2} }{18 x^{2} -6xy} = \frac{ y^{2}- (3x)^{2} }{6x(3x-y)}=\frac{ (y-3x)(y+3x) }{-6x(y-3x)}= -\frac{y+3x}{6x}$

Answer 2

$\frac{y ^{2} -9 x^{2} }{18 x^{2} -6xy} = \frac{(y-3x)(y+3x)}{6x(3x-y)} =- \frac{(y-3x)(y+3x)}{6x(y-3x)} = \\ \\ =- \frac{y+3x}{6x}$