Question

(1/2)x×(x+1+x+0.4)=0.78解这个方程,

Answer 1

(1/2)x×(x+1+x+0.4)=0.78

(1/2)x×(2x+1.4)=0.78

x^2+0.7x-0.78=0

(x-0.6)(x+1.3)=0

x-0.6=0,x+1.3=0

x=0.6,x=-1.3