Answer:
y=3x-3
Explanation:
since the line must pass through (0,-3), you must have the second number (or y intercept) in the equation be -3. since the slope must be 3 then it will be shown as 3x. put it all together to get y=3x-3. not sure what the -1 is doing there but y=3x-3 passes through (0,-3)