若[3X+2Y-5]与2X-5Y-16
来源:学生作业帮助网 编辑:作业帮 时间:2024/07/07 09:35:30
方程组一式加二倍的二式,得X=2m–1带入二式,Y=–2m4,再带入不等式,剩下的自己算吧再问:答案是多少?验算一下再答:x+2Y=2m-1+2(-2m+4)7/2
|2-x|+|x-y+4|=02-x=0,x-y+4=0x=2,2-y+4=0,y=63(x-y)-5(x-y)^2-3(x-y)+(y-x)^2+4(x+y)^2+3(y-x)=-4(x-y)^2+
根据方程式可以得出方程组:3x+2y=175x-y=-2解此方程得:x=1y=7解方程不用我说了吧,2式乘2再加上1式可以解出x
[(x+2y)(x-2y)-(2x-y)^2+(3x-y))2x-5y)]/(-x)=(x²-4y²)-(4x²-4xy+y²)+(6x²-17xy+
x与y互为相反数x+y=0又2x-3y=52x-3(-x)=55x=5x=1y=-1x+3y2=1+3*(-1)^2=1+3=4
欲使两个单项式的差仍为单项式,这两个单项式必须是同类项.所以x+5=yx+y=2--x整理一下即:x--y=--5(1)2x+y=2(2)(1)+(2)得:3x=--3x=--1把x=--1代入(2)
因为(x-y)/(x+y)=3,则(x+y)/(x-y)=1/3则5(x-y)(x+y)-(x+y)/2(x-y)=5*3-1/(3*2)=15-1/6=89/6
(x-y)^5*(y-x)^3*(x-y)^2=-(x-y)^5*(x-y)^3*(x-y)^2=-(x-y)^(5+3+2)=-(x-y)^10
(1)x/(x^2+2xy+y^2)与y/(x+y)x/(x+y)²与y(x+y)/(x+y)²(2)(x+4)/(x^2+4x)与(x-5)/x(x-5)-2(x-5)(x+4)
3x-5y=0,则x+y/x=(8/5),x-y/y=(2/3),2x-3y/2x+3y=(1/19)因为3x-5y=0所以3x=5y设x=5,y=3,可以解得3x-5y=0,则x+y/x=(8/5)
x-y=a+32x+y=53x=a+8x=(a+8)/3>0a>-8y=-(2a+1)/3-1/2所以a>-1/2
则,/x+y-3/+√(2x+3y-5)=0由于绝对值与被开偶次方数都具有非负性,且0+0=0,所以,x+y-3=02x+3y-5=0解之,得:x=4,y=-1
2x+3y=52x-3x=5x=-5y=5
若x-y/x+y=5则x-y=5(x+y)所以求x-y/2x+2y+5x+5y/3x-3y=5(x+y)/[2(x+y)]+5(x+y)/3(x-y)=5/2+5(x+y)/[3*5(x+y)]=5/
解(x-y)(x+y)-(x-2y)²+x(3x-5y)-(x-y)(x-2y)=(x²-y²)-(x²-4xy+4y²)+(3x²-5xy
x(x*x-1)+x(5-x*x)-6y+7=-x+5x-6y+7=2(2x-3y)+7=2*(-4)+7=-8+7=-1再问:能在写详一点吗-x+5x-6y+7再答:x(x*x-1)+x(5-x*x
(2X-3y)-(5x-y)=2x-3y-5x+y=2x-5x-3y+y=(2x-5x)+(-3y+y)=-3x-2y这样写总是全过程了吧
哦……好像是成反比例的.x:y就等于三分之二:五分之三.那么x乘Y应该就是三分之二乘五分之三咯……那不就是反比例啦
|x+5|与(x+2y-3)^2互为相反数且他们本身都大于等于0要互为相反数只能他们都为0所以x+5=0x=-5x+2y-3=0所以y=4
X与Y互为相反数,就是说X+Y=0,Y=-X,将其带入原方程,3x^2+5x-2(-x)^2+3(-x)-8=0,化简得x^2+2x-8=0,解一元二次方程得x=2或x=-4