Question

解一元二次方程 有分（30-x0.5）×（10+x）-（30-x0.5）×1-x0.5×0.5=275,

Answer 1

(30-0.5*X)*(10+X)-(30-0.5*X)*1-0.5*0.5*X=275

(30-0.5*X)*(9+X)-0.25*X=275

270-4.5*X+30*X-0.5*X^2-0.25*X=275

270+25.25*X-0.5*X^2=275

0.5*X^2-25.25*X+5=0

X^2-50.5+10=0

X1=25.25+(25.25^2-10)^0.5=25.25+627.5625^0.5

X2=25.25-(25.25^2-10)^0.5=25.25-627.5625^0.5