减去-2x等于-3-搜答案-拍题作业网

x²-5x=14x²-5x-14=0(x-7)(x+2)=0x1=7x=-2x²-3x+2=7²-3x7+2=30或x²-3x+2=（-2）²

假设y=x+2则原式化为:y^2-2y-3=0所以,(y-3)(y+1)=0所以,y=3或y=-1所以,x+2=3或x+2=-1所以,x=1或x=-3

2x的平方减去3x减去2等于02X^2-3X-2=0(2X+1)(X-2)=0X1=-1/2,X2=2

x的平方减去3x加1等于0求2x的平方减去6x加3x²-3x+1=0两边同乘以2得：2x²-6x+2=0两侧同加上1得：2x²-6x+3=1所以：2x²-6x+

x²-2x-3=0x²-2x=3x²-2x+1=4(x-1)²=(±2)²x-1=±2x=-1,x=3

2x²-3x-2=(2x²-4x)+(x-2)=2x(x-2)+(x-2)=(2x+1)(x-2)

把x移到一边3分之2减3等于8x减2分之1x-7/3=15x/2x=-14/45

由2x^2-3x-4=0得：x^2-2=3x/2所以x-2/x=(x^2-2)/x=(3x/2)/x=3/2

x²-6x-1=0x²-6x=1x²-6x+9=1+9=10(x-3)²=(±√10)²x-3=±√10x1=3+√10,x2=3-√10|√27-6

-3-5x+4x²+-3x+2x²=6x²-8x-3

-3-5x+4x²+-3x+2x²=6x²-8x-3肯定是对的.

解分式方程输入很辛苦.经检验X=7/2是原方程的解.

4（x+y)-3(x-y)=14x+7y=14(x+y)/2+(x-y)/3=6两边同乘以6,得3(x+y)+2(x-y)=365x+y=36则x+7(36-5x)=14x=7,y=1

(5/12-1/4）*x=1/31/6*x=1/3x=22/3-8x=x/22/3=8.5xx=1/51

(x-1)/3-(x+2)/6=(4-x)/2等式两边同乘6得：2(x-1)-(x+2)=3(4-x)去括号：2x-2-x-2=12-3x移项：4x=16x=4

x-(x-1)/2=2-(x+2)/3等式两边同时乘以6得6x-3(x-1)=12-2(x+2)6x-3x+3=12-2x-43x+3=8-2x5x=5x=1

(x^2-1)/2-(x-2)/3=x^23x^2-3-2(x-2)=6x^23x^2-3-2x+4=6x^23x^2+2x-1=0(3x-1)(x+1)=0所以x=1/3或x=-1

(x-1)(x-3)(x-4)(x-5)-(x-1)(x-2)(x-3)(x-5)=(x-1)(x-2)(x-4)(x-5)-(x-1)(x-2)(x-3)(x-4)(x-1)(x-3)(x-5)(x

5x+6-2+3x=28x=2-6+28x=-2x=-2.5