x`2+(20-x)`2=17怎么算

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x`2+(20-x)`2=17怎么算x`2+(20-x)`2=17怎么算x`2+(20-x)`2=17怎么算x^2+(20-x)^2=17,x^2+400-40x+x^2=17,2x^2-40x+38

x`2+(20-x)`2=17怎么算
x`2+(20-x)`2=17怎么算

x`2+(20-x)`2=17怎么算
x^2+(20-x)^2=17,
x^2+400-40x+x^2=17,
2x^2-40x+383=0,
然后可利用求根公式去计算.

‘是什么意思

x^2+(20-x)^2=17
x^2+400-40x+x^2=17
2x^2-40x+383=0
b^2-4ac=40^2-4*2*383=-1464
这个方程无实根。