Basically you have to use the table to find the equation of the line, then plug in a point into x and y and the b you will get is your y-intercept.
Now if you are familiar with the equation of a line in slope intercept form, it will look like this: y=mx+b. Here the ‘m’ is the slope and the ‘b’ is your y-intercept. What you need to do is use any two points given from the table and find the slope. To do that follow the steps below:
1. Pick two points. Let’s take the first two.
(-28, -54) And (-21, -40)
2. Subtract the two y values, -40 - (-54) = 14
3. Subtract the two x values, -21 - (-28) = 7
4. Now take your answer from step 2 and divide it by your answer in step 3. This will be 14/7, which will be 2.
Your answer from step 4 is your slope, or ‘m’.
(That series of steps was basically change in y over change in x, you can look that up if you are still confused)
Now that you know m, your incomplete equation will be this:
y=2x+b.
Next you will pick any point from the table again, and replace it with x and y in the equation. Let’s pick the second point, (-21,-40)
Plug this in: -40 = 2(-21) + b
Solve for b and you will get your answer.
-40 = -42 + b
b=2
Your answer is 2, that is the y intercept.
(The full equation of the line from that table would be y=2x+2)
Hope this helps!
