(100-2X)(90-X)=8448

分类: 作业答案 • 2021-12-31 11:36:01

问题描述：

(100-2X)(90-X)=8448

答

(100-2X)(90-X)=8448
2x²-280x+9000=8448
2x²-280x+552=0
x²-140x+276=0
(x-2)(x-138)=0
x1=2 x2=138