Start with the line equation and put it into slope intercept format:
-7x -4y = -4 (solve for y)
-7x + 4 = 4y
y = -7/4x + 1
The slope of the line is -7/4. To get a perpendicular line you need the negative reciprical. Flip the slope and change the sign.
Perpendicular line slope is 4/7.
Use the point now (-14, -3) and slope = 4/7.
y - -3 = 4/7(x - -14)
y + 3 = 4/7x + 14*4/7
y + 3 = 4/7x + 8
y = 4/7x + 8 - 3
y = 4/7x + 5