x/4+y/3=-1和5(x-8)=6(y+9)怎么解?

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x/4+y/3=-1和5(x-8)=6(y+9)怎么解?

x/4+y/3=-1和5(x-8)=6(y+9)怎么解?
x/4+y/3=-1和5(x-8)=6(y+9)怎么解?

x/4+y/3=-1和5(x-8)=6(y+9)怎么解?
x/4+y/3=-1
两边乘12
3x+4y=-12 (1)
5(x-8)=6(y+9)
5x-40=6y+54
5x-6y=94 (2)
(1)×3+(2)×2
9x+12y+10x-12y=-36+188
19x=152
x=8
y=(-12-3x)/4=-9

1. 把下列多项式分解因式:
(1) 3x+3y
=3(x+y)
(2) -24m^2x-16n^2x;
=-8x(m^2+2n^2)
(3) x^2-1
=(x+1)(x-1)
(4) (xy)^2-1;
=(xy+1)(xy-1)
(5) a^4x^2-a^4y^2
=a^4(x^2-y^2)
=a^...

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1. 把下列多项式分解因式:
(1) 3x+3y
=3(x+y)
(2) -24m^2x-16n^2x;
=-8x(m^2+2n^2)
(3) x^2-1
=(x+1)(x-1)
(4) (xy)^2-1;
=(xy+1)(xy-1)
(5) a^4x^2-a^4y^2
=a^4(x^2-y^2)
=a^4(x+y)(x-y)
(6) 3x^2+6xy+3y^2;
=3(x^2+2xy+y62)
=3(x+y)^2
(7) (x-y)^2+4xy
=x^2-2xy+y^2+4xy
=x^2+2xy+y^2
=(x+y)^2
(8) 4a^2-3b(4a-3b).
=4a^2-12ab+9b^2
=(2a-3b)^2
2.2x(a-2)-y(2-a)
=2x(a-2)+y(a-2)
=(a-2)(2x+y)
=(0.5-2)*(2*1.5-2)
=-1.5*1
=-1.5

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{x+y=1 ,xy=-6{x(2x-3)=0,y=x²-1{(3x+4y-3)(3x+4y+3)=0,3x+2y=5{(x-y+2)(x+y)=0,x²+y²=8{(x+y)((x+y-1)=0,(x-y)(x-y-1)=0 x+y=1 5x-2y=8 3x-y=7 2x-y=3x表示y和用y表示x 求解简单的二元一次方程组x=3y-2和y=2x-y 2x=3y-12和4y=2x+1 3x-13y=-12和x+3y=2 2x-5y+13=0和9x+6y-8=0 x/4+y/3=-1和5(x-8)=6(y+9)怎么解? 已知X,Y,满足(X+3Y)(X-3Y)=-10(Y^2-6/5)和2X(Y-1)+4(1/2X-1)=0 (X+Y)^2 X^2Y+XY^2注:*/* 是分数 解方程组3(x+y)-4(x-y)=4和(x+y)/2+(x-y)/6=1kkkkkkkk (2x-2y)/3-(x-y)=-1和6(x+y)-4(2x-y)=16 二次函数与x轴交点y轴交点坐标(1)y=-2x²+8x-8:(2)y=1/2 x²-4x+3:(3)y=-3x²+12x-3:(4)y=4x²-24x+26:(5)y=2x²+8x-6:(6)y=1/2x²-2x-1 求x轴交点和y轴交点坐标和最值 数学. 方程组解答 1、y=2x-5和x+3y=-1 2、2y-8=-x和4x+3y=7 若2x-3y+4=0则x(x*x-1)+x(5-x*x)-6y+7 求定义域和值域(1)y=-2x(2)y=x+3(3)y=-2/x(4)y=x²+2x+1(5)y=-x²+4x+6 9x=8x-6 ,8y=4y+1 ,0.6x=3+1/3x和0.02x=0.8x-7. 利用关系式判断,y和x成什么比例 8x=y( ) x/4=y( ) y/8=5/x( ) 1/x=y( )快 求x和y,(1)3x+4y=5 (2)-7x+9y=-6 (3)3x-y=9 解下列方程组或不等式组...一{ x(x-5)+y(y+6)=x平方+y平方-39 二 { x(x+7)-y(y-8)=x平方-y平方-11一{x(2x-5)大于2x平方-3x-4二{(x+1)(x-3)+8x大于(x+5)(x-5)-2 例X=1 y=21.X+Y=5 X-Y=15 2.2X+3Y=4 5X+6Y=7 3.X+3Y=5 3X+Y=-1 4.2X+Y=3 3X+5Y=11 5.4X+3Y=6 2X+Y=4 6.X+Y=180 X=3Y-10 7.3X-2Y=3 2X-Y=7 8.5X+3Y=7Y X+Y=45 9.3X+4Y=126X+8Y=24 X:6Y=1:4 10.X+Y=138 X-45=Y+53 11.X+Y=60 14Y=20X 12.2X+3Y=15.5 5X+6Y=35 13.X+Y=170 3 (x-2y)(x+y)-2x(-2x-3y)+6x(-x-y),其中x=-1,y=2要讲解和答题 {3(x+y)-4(x-y)=4 {x+y/2 + x-y/6=1