12Xx25％+（3200-12X）x20％=700

12Xx25％+（3200-12X）x20％=700 12Xx25％+（3200-12X）x20％=700 5X+45=7X+3 12Xx25％+（3200-12X）x20％=700 (580-x)+[600-(x+272)]=444 12Xx25％+（3200-12X）x20％=700 5X+45=7X+3 (580-x)+[600-(x+272)]=444 每1步运算都要说.12Xx25％+（3200-12X）x20％=700 5X+45=7X+3 (580-x)+[600-(x+272)]=444 因式分解(x2-x)(x2-x-8)+12 x2+x-12因式分解 解一元二次方程,谢x2+12x=0,4x2-1=0,x2=7x,x2-4x-21=0,（x-1）（x+3）=12,3x2+2x-1=0 DIvide x3+x2-14x-24 by x+2Solution x2-x-12/)x-2)x3+x2-14x-24x3+2x/-2x2-14x-x2-2x/-12x-24-12x-24/0In this example we see that x+2 is a factor of x3+x2-14x-24,as the remainder is zero.Thus x3+x2-14x-24÷（x+2）=x2-x-12 with zero remainderso x3+x2-14x 解方程(x2+x+1)(x2+x+12)=42 因式分解(x2+x+1)(x2+x+2)-12= 因式分解:（x2+8x+12)(x2+8x+10) (x2-2x)2-7(x2-2x)+12 (x2-2x)2-7(x2-2x)+12因式分解 (x2+6x+8)(x2+14x+48)+12 因式分解x2+4x-12 （x2-3）（x2-2)-2十字相乘法做 (x2+3x+2)(x2+7x+12)-24十字相乘法做 (x2+5x+2)(x2+5x+3)-12怎么因式分解 (x2)是x的平方, 解方程：1/x2+x +1/x2+3x+2 +1/x2+5x+6 +1/x2+7x+12 +1/x2+9x+20=5/x2+11x-708解方程：1/x2+x +1/x2+3x+2 +1/x2+5x+6 +1/x2+7x+12 +1/x2+9x+20=5/x2+11x-708