Verified Answer :

\(3y-4x=12\\ 3y=4x+12\\ y=\frac{4}{3}x+4\\\\ \boxed{m=\frac{4}{3}}\)

\(3y-4x=12 \ \ \ /:3 \\ 3y:3-4x:3=12:3 \\ y- \frac{4}{3}x=4 \ \ \ /+ \frac{4}{3}x \\ y=4+ \frac{4}{3} x \\ y=\frac{4}{3}x+4\)
y = mx + b, where:
m - slope 
b - y-intercept 
Well:
The slope is \(\frac{4}{3}\)