3分之2(x-y)=4分之x+y-1
来源:学生作业帮助网 编辑:作业帮 时间:2024/05/02 04:32:36
2分之(x+y)+3分之(x-y)=13,(1)3分之(x+y)-4分之(x-y)=3(2)(1)×4+(2)×3得:2(x+y)+(x+y)=52+9;3(x+y)=61;x+y=61/3=122/
=(2X/3Y)*(3X/4Y)*(4/xy)=(2x*3x*4)/(3y*4y*xy)=2x/(y^3)
(2X)/3+(3Y)/4=1/5(5X)/6-(5Y)/2=2(2X)*4+(3Y)*3=12/5(5X)-(5Y)*3=1240*X+45*Y=125*X-15*Y=1215*X-45*Y=365
x=5,y=8再问:过程打一下再答:(x+15)(y-6)=(x-1)(y+2)xy-6x+15y-90=xy+2x-y-216y=8x+882y=x+114x-xy=x-3-xy+3y3x=-3+3
(3x²/4y)²×(2y/3x)+(x²/2y²)÷(2y²/x)=(9x⁴/16y²)×(2y/3x)+(x²/2
2:=19y或12(2/3)x或19(3/4)z3:④>②>③>①再问:过程再答:2:代入未知数一步步倒3:设极值a的绝对值=1那么a=1或者-1同理,b=2或者-2,那四个数每个数都把a,b代入其中
3)把①式乘以10,②式乘以6,得:25x+2y=-402x+y=1由下式得y=1-2x,代入上式得25x+2-4x=-4021x=-42x=-2则y=1+4=54)把①式乘以6,②式乘以2得3x-y
①方程乘以18得9x+6y=117③②方程乘以24得8x-6y=36④③+④得x=9带入①得y=6
2.代入x、y得方程组:a+b+c=0(1)4a+2b+c=3(2)9a+3b+c=28(3)把(1)c=-a-b代入(2)(3),得3a+b=3(4)8a+2b=28(5)2*(4)-(5)得-2a
(3x+2y)/4=(2x+y)/5(3x+2y)/4=(x-y+1)/6去分母化简得到:5(3x+2y)=4(2x+y)6(3x+2y)=4(x-y+1)去括号移向化简得7x=-6yx=2/7-8y
9分之5x+4y等于5分之3x+2y等于2分之x-y(同时乘以90,得到)50X+40Y=54X+36Y=45X-45Y所以X=Y=0
3x/4+2y=(2x+y)/5=(x-y+1)/6则3x/4+2y=(2x+y)/5―→15x+40y=8x+4y→7x+36y=0――①(2x+y)/5=(x-y+1)/6―→12x+6y再问:麻
第一个两边乘128(x-y)-3(x+y)=-128x-8y-3x-3y=-125x-11y=-12(1)第二个6x+6y-8x+4y=16-2x+10y=16x-5y=-8(2)(1)-(2)×55
=3x/(x-4y)-(x+y)/(x-4y)-7y/(x-4y)=(3x-x-y-7y)/(x-4y)=(2x-8y)/(x-4y)=2(x-4y)/(x-4y)=2
因为:3分之x+1=4分之y+3=5分之x+y,所以:(x+1)/3=(y+3)/4=(x+y)/54x+4=3y+94x=3y+55x+5=3x+3y2x=3y-5x=5y=5则x+2y+3分之3x
x-4y分之3x+4y-x分之x+y-x-4y分之7y=3x/(x-4y)-(x+y)/(x-4y)-7y/(x-4y)=(3x-x-y-7y)/(x-4y)=(2x-8y)/(x-4y)=2
x分之4+y分之3=10x分之9-y分之7=-54/x-3/y=10①9/x-7/y=-5②①*123x-4y=120③②*637x-9y=-315④③*36108x-144y=120⑤④*428x-
原式等价于10(x+1)=5(y+3)=4(x+y)10(x+1)=5(y+3)可得2x-y=15(y+3)=4(x+y)可得4x-y=15解得x=7y=13x+2y+3=363x+2y+1=48两式
解方程组(X/2)+Y=2/3X-Y+4=(X/4)+2Y+3方程组变形得:3x+6y==4(1)3x-12y==-4(2)由(1)-(2)得:18y==8y==4/9由(1)*2+(2)得:9x==