Respuesta :

the slope of y=2x-4 is 2, the y-intercept is -4
y=mx+b is the formula
m=slope
b=y-intercept

2 is the slope that's your answer so how did i get this is the y=mx+b formula 

m is your slope

b is your y intercept

and the y is the y axis. so I hope this helped mark this the brainiest if this helped. ^^ 
Have a good day. ~Shado