Write in slope-intercept first.
Find the y-intercept.
y = -2x + b
3 = -2(4) + b
3 = -8 + b
3 + 8 = -8 + b + 8
11 = b
Now, write in slope-intercept form.
y = -2x + 11
Now, solve for standard form.
y - 11 = -2x + 11 - 11
y - 11 = 2x
y + (-11) - y = -2x - y
-11 = -2x - y
-2x - y = -11 (Answer)
Hope This Helped! Good Luck!