x|15|30 |45 |75|60 |1号( )|2号( ) y|2 |3号( )|4号( )|10|5号( )|12
解方程组:(0.2x+0.1y)/2- (4x-y)/10=(x-y)/5+ (3x+0.5y)/30 (3x+2y-1
10/x+y+3/x-y=-5 15/x+y-2/x-y=-1(用换元法解此方程组)
解方程组(1)2x-3y=10,-4x+y=5 (2)3x-2y=15,5x-4y=23
5/12[-4/3(x-y)^3] *(x+y)^2 * (-x-y)^3 * 5/6(y-x)^2
(3x-y)²-2x(4x-5y)-(x+2y)²
(1)y+3x+17=0 5y-2x+17=0 (2)x+y+z=12 x+2y+5z=22 x=4y (3)x+y+z
[(2x^2+y)^2-5y^2(3x^2+1)-4(x^2+y)(x^-y)]÷5x^y,其中x=99,y=15分之2
(-2x^4y^5)^3*(-3x^3y^2)^2\(-12x^10y^10)
数学二元一次方程 (x-y=2,2x+y=4 ) (x-y=1,3x-y=5) (x-y=8,3x+y=12 ) (a+
1.((y+2x)(-2x+y)+4(x+2y)^2)/3y 2.(2(x-y)^3-8(x-y)^2(x+y)+6y(
解下列二元一次方程组(1)4x+3y=1,3x-4y=-18(2)5x-y=10,2x+3y=13(3)7x+3y=15
用换元法解方程组:﹛(x+y)分之10+(x-y)分之3=-5 ﹛(x+y) 分之15 -(x-y) 分之2=-1