{7x=8x;2x=3y-1500} 解方程

1.解方程组{x+y=7,3x+y=172.{x+y=4,2x-y=53.{3x+2y=5x+2,2（3x+2y)=2x+8 3x+2=y 5x+4=y 7x+6=y 9x+8=y 11x=y怎么解 x+y=1 5x-2y=8 3x-y=7 2x-y=3x表示y和用y表示x 已知实数x.y满足根号(x+y-8)+根号(8-x-y)=根号(3x-y-4)+根号(x-2y+7),求x,y {7x=8x;2x=3y-1500} 解方程 解联立方程组 x/x+y=5/8 x/x+y+6=2/3 用递归法求y=x-(x*x*x/3!)+(x*x*x*x*x/5!)-(x*x*x*x*x*x*x/7!)+. 【2(x-y)^3-8(x-y)^2(x+y)+6y(x-y)^2】/2(x-y)^2= 解方程组(x+y)(x-2y)=-5 (x-y)(x+2y)=7 若(x-y)/(x+y)=3 则(x+2y)/(6x-7y)等于 初二计算 解方程 不等式组(1)4(y-z）^2-(2y+z)(-z+2y) (2)(x(x^2y^2-xy)-y(x^2+x^3y)/4x^2y (1)(x+7)(x+5)-(x-1)(x+5)=42 (2)x(2x-5)＞(x-1)(2x-1）-7 (x+1)(x+3)+8x＞(x+5)(x-5)-2 3^x+2x=y,x 解方程组8y+5x=84y-3x=7 方程组 因式分解 4x^3-4x^2y-(x-y) 解方程组1.x+1/3=5x-y/5 7y=5x+25 (x=2,y=5) 2.2x-y/5=x+y/3=3(x=8,y=1) 用适当的方程解方程组2(x+y)-(x-y)=8 (x+y)-2(x-y)=15 2x+1=5(y+2) (3x+2)-2(y+7x)=16 2x-y=7,3x+y=8 3(x+y)-2(x-y)=4; 3(x+y)+2x-2y=8 3(x+y)-2(x-y)=4; 3(x+y)+2x-2y=8 解方程组 若2x-3y+4=0则x（x*x-1)+x(5-x*x)-6y+7