Answer: y = -x -2
Step-by-step explanation:
1. Usually I want to find the slope first, so you put your points (1, -3) and (3, -3) and turn it into a rise over run form with the y-intercept representing rise and the x-intercept representing the run. For your points the rise over run forms would be -3/1 (-3 over 1) and -5/3 (-5 over 3).
2. Next, you subtract your second point from your first point, this will get you your slope: -5/3 minus -3/1. If you do the math your answer will be -2/2, which simplifies to -1 and this is your slope. In the y = mx + b format, the -1 would be the m, since that's the slope. So now, your current equation would be y = -x + b.
3. Now, we want to find the y-intercept or the starting point, which is b in the equation. You can use either of your points to find the b. I used (1, -3) and made it into the equation -3 = -x(1) + b. If you solve this like a regular equation you get -2 = b, which is your y-intercept. This makes your equation y = -x -2. And that's in the slope intercept form.
4. If you want to check the answer you could use any of your points and plug it into the equation and see if it is true. Usually I'd just put the x-intercept in the equation and solve to see if it equals the y-intercept you have in your points. For example: y = -x(1) -2. Check this and you should get y = 1.
