Remember that slope-intercept form is y=mx+b.
First, add 2x on each side to get [tex]-4y=2x+28[/tex]
Then, divide by -4 on each side, and the equation will be [tex]y=- \frac{1}{2} x-7[/tex]
Looking back in the equation y=mx+b, comparing it to [tex]y=- \frac{1}{2} x-7[/tex], we see that [tex]m=- \frac{1}{2} [/tex] and b = -7.