Вроде бы так, ну точно не знаю
(10+2√10)/√10=(10+2√10)/√10 * √10/√10=(10√10+20)/10= =10(√10+2)/10=√10 +2
(x-9)/(x-6√x +9)=(√x-3)(√x+3) /(√x-3)²=(√x+3)/(√x-3)=(√x+3)/(√x-3)
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
1) xy-5x+3y-15=x(y-5)+3(y-5)=(x+3)(y-5)
2) x^{2}-3x+2x-6=x(x-3)+ 2(x-3)=(x+2)(x-3)
x^{2}-3x+2x-6=x(x+2)-3(x+2)=(x-3)(x+2)
3) xy+4y-3x-12=(x+4)(y-3)
4) x^{3}+7x^{2}-xy-7y=x^{2}(x+7)-y(x+7)=(x^{2}-y)(x+7)