初一数学去括号题10道(1)(3x-5y)-(6x+7y)+(9x-2y)(2)2a-[3b-5a-(3a-5b)](3)(6m2n-5mn2)-6(m2n-mn2)(4)(3x+4y)-(x-y)-(6x-2y)(5)(8x-3y)-(4x+3y-z)+2z;(6)-5x²+(5x-8x...
7(2x-1)-3(4x-1)=4(3x+2)-1;(5y+1)+(1-y)=(9y+1)+(1-3y);20%+(1-20%)(320-x)=320×402(x-2)+2=x+12(x-2)-3(4x-1)=9(1-x)x/3-5=(5-x)/22(x+1)/3=5(x+...
7(2x-1)-3(4x-1)=4(3x+2)-1;(5y+1)+(1-y)=(9y+1)+(1-3y);20%+(1-20%)(320-x)=320×402(x-2)+2=x+12(x-2)-3(4x-1)=9(1-x)x/3-5=(5-x)/22(x+1)/3=5(x+...
(3)(6m2n-5mn2)-6(m2n-mn2)解:(1)(3x-5y)-(6x+7y)+(9x-2y)=3x-5y-6x-7y+9x-2y(正确去掉括号)=(3-6+9)x+(-5-7-2)y(合并同类项)=6x-14y(2)2a-[3b-5a-(3a-5b)](应按小括号...
初一数学方程题谁能给我50道自己找初一数学方程组速。2y-2x+1=04y-4x+2=04y-4x+2+4x+y-1=0y=-0.2x=0.3初一数学方程组计算{3(X+Y)=126(1)去括号:3X+3Y=126(1)4(X+10)=5Y+20(2)去括...
1.有这样一道题“当a=0.5.b=-0.28时,求多项式7a3-6a3b+3a2b+3a3+6a3b-3a2b-10a3+3的值”,有一位同学指出,题中给出的条件是多余的,他的说法有道理吗?2.已知A=x2+xy+y2,B=-3xy-x2计算(1)B...
所以x=0y=5(这道题时间为80秒与实际不符)3、设A点距北山的距离为x,车返回到乙组时,乙距出发点距离为y那么[x-4*(18-x-y)/60]/4=(18-y)/60y/4=(18-x)/60+(18-x-y)/60所以x=2y=...
20X-50=5028+6X=8832-22X=1024-3X=310X*(5+1)=6099X=100-XX+3=18X-6=1256-2X=204y+2=6x+32=763x+6=1816+8x=402x-8=84x-3*9=298x-3x=105x-6*5=42x+5=72x...
1.2(x-2)-3(4x-1)=9(1-x)2.11x+-2x=100-9x3.15-(8-5x)=7x+(4-3x)4.3(x-7)-2[9-4(2-x)]=225.3/2[2/3(1/4x-1)-2]-x=26.2(x-2)+2=x+17.0.4(x-0.2)+1.5=0...
1.去括号:5x-5=1移项:5x=1+5合并同类项:5x=6系数化为一:x=6/52.2-1+x=-2x=-2-2+1x=-33.11x+1=10x+511x-10x=5-1x=44.4x-60+3x=34x+3x=3+607x=63x=95.5x+40-5=...