1....2X的平方+7x+3=0
2....3X的平方+2x-5=0
(以上有因式法求,)
(交叉相乘,驗中項,橫向寫出兩因式)
1. 2x²+7x+3=0 (2x+1)(x+3)=0 x1=-1/2 x2=-3
2 3x²+2x-5=0 (3x+5)(x-1)=0 x1=-5/3 x2=1