You will need to use the line equation in the point-intercept form that is represented as:
y - yo = m.(x - xo)
Where:
xo, yo -> Point coordinate
P (-3,5)
m -> Slope = -4
Calculating:
-> y - 5 = -4.(x - (-3))
-> y - 5 = -4.(x + 3)
-> y - 5 = -4x - 12
-> y = -4x - 12 + 5
-> y = -4x - 7
or...
-> 4x + y + 7 = 0