(x/4)(x/4)+(20-x/4)(20-x/4)=11
问题描述:
(x/4)(x/4)+(20-x/4)(20-x/4)=11
答
两边乘16
x²+(20-x)²=176
2x²-40x+400=176
x²-20x+112=0
判别式小于0,无解