Question

X(2X-4)=5-8x

用求根公式发解这个方程。要步骤、

Answer 1

解:2x�0�5-4x=5-8x 2x�0�5+4x-5=0a=2 , b=4 , c=-5△=b�0�5-4ac=16-4×2×(-5)=56x=(—4±根号56)/4x1=—1+(根号14)/2, x2=—1—(根号14)/2

Answer 2

x(2x-4)=5-8x
2x^2-4x-5+8x=0
2x^2+4x-5=0
2(x^2+2x+1)-7=0
2(x+1)^2=7
(x+1)^2=7/2
x=±√14/2-1

Answer 3

2x�0�5+4x-5=0x=[-4±√(4�0�5+4×2×5)]/(2×2)=（-2±√14）/2