3 is the scale factor you would use to dilate Figure A to Figure B.
The standard form:

The slope-intercept form:

m - slope
b - y-intercept
We have m = 3 and b = -5.
Substitute:
subtract 3x from both sides
change the signs

Answer:
y=-4x+9
Step-by-step explanation:
-4 is the slope and the y intercept is 9