16x^2+()+9y^2=()^2

x-y/x-x+y/y-(x+y)(x-y)/y² y/x=2 4(x-y)-3(x-y)=9 5(x-y)+2(x-y)=11 3(x+y)-2(x-y)=11 4(x+y)+3(x-y)=9 (x-4)+2=(Y-X)+(16-Y) X=9 但是Y=? 先化简再求值 x(9x-y)-y(y-x)+(x-y)的平方,其中x=-1,y=2 已知x^2+xy=16 y^2+xy=9 求(x+y) (x-y)分别是 x+y x-y 不是乘 (12-2x)/X=(-16-2Y)/Y X^2+Y^2=25 Y {5(x-3y)-6=2x+1 3(x+6y)+4=9y+19 ｛3分之2（x-y）=4分之x+y-1 6）x+y)=4(2x-y)+16 填空：x-y/x+y=( )/x^2-y^2 （x-y)2•(y-x)³(x-y)=? 9y=3x-(x-1),4(x+y)-(2x+4)=8y 5x=3y,(2x+y)的平方=5x(x+y)+9 已知2x-y/x+2y=3,求2(2x-y)/x+2y-9(x+2y)/2x-y+3的值. 3x-2y=9 x-3y=2 x+y=5 x+2y=3 y=x 2x+y=8 因式分解：(x+y)^3(x-y)-(x+y)(x-y)^3,9x^2-16(a+b)^2 若x-y=1 化简（x+y)(x^2+y^2)(x^4+y^4)(x^8+y^8)(x^16+y^16) y+y'-2y=2x 3y=2x y/3=x/2 12/x=9/y y/x=?y/x=?x/y=?