Question

срочно! алгебра 7 кл

Answer 1

1) 25x2-36y2/10x2+12xy*8xy/24y2-20xy=
= ---(5x-6y)(5x+6y)/2x(5x+6y)*8xy/4y(5x-6y)= 8xy/8xy=-1
2) 9a2-16b2/6a+8b*6a/12b-9a= ---(3a-4b)(3a+4b)/2(3a+4b)*6a2/3(3a-4b)=6a2/6=-a2
3) 4a2-20ab+25b2/5b+46:(2a-5b)2/25b2-16= (2a-5b)2/(5b+4)*(5b+4)(5b-4)/(2a-5b)2= 5b-4