Hello!
Let's start by finding the slope of the line. You can calculate the slope by dividing the change in y-values by the change in x-values using the following formula:

The plotted coordinates are (0, 5) and (4, -5); let's plug those into the formula:

Simplify:



The slope is

.
Now, the y-intercept is where the line intersects the y-axis, or when x equals 0. x equals 0 when y equals 5, so the y-intercept is 5.
I hope this helps!