∵(2m+1)y=7m+4
∴y=(7m+4)/(2m+1)
∴x^2-4x+2+[(7m+4)/(2m+1)]^2=0
△=b^2-4ac
=16-4[(7m+4)/(2m+1)]^2
=-(132m^2+160m+48)/(2m+1)^2
∴无论m取何值,△
∵(2m+1)y=7m+4
∴y=(7m+4)/(2m+1)
∴x^2-4x+2+[(7m+4)/(2m+1)]^2=0
△=b^2-4ac
=16-4[(7m+4)/(2m+1)]^2
=-(132m^2+160m+48)/(2m+1)^2
∴无论m取何值,△