解个方程.7x-2x^2=-27x-2x^2=-2求x的值
问题描述:
解个方程.7x-2x^2=-2
7x-2x^2=-2
求x的值
答
7X-2X^2=-2
-2X^2+7X+2=0
2X^2-7X-2=0
X1=(7+根号65)/4
X2=(7-根号65)/4
答
(-7+根号65)/-4
(-7-根号65)/-4