X-[1/4x+(1/4x+4)]=19
问题描述:
X-[1/4x+(1/4x+4)]=19
答
X-[1/4x+(1/4x+4)]=19
1/4x+(1/4x+4)=x-19
1/4x+4=x-19 - 1/4x
1/4x+4 +1/4x=x-19
4 + 1/2x = x -19
1/2x = x - 23
1 = 2x² - 46x
2x² - 46x -1 = 0
x = 46±根号( 2116+ 8) / 4
= (46±根号2124 ) / 4
= (46±2根号531 ) / 4
=(23±根号531 ) / 2
答
X-[1/4x+(1/4x+4)]=19
X-[1/2x+4)]=19
1/2x-4=19
1/2x=23
x=46