For this case we have that by definition, the equation of a line of the slope-intersection form is given by:
![y = mx + b](https://tex.z-dn.net/?f=y%20%3D%20mx%20%2B%20b)
Where:
m: It's the slope
b: It is the cut-off point with the y axis
While the point-slope equation of a line is given by:
![y-y_ {0} = m (x-x_ {0})](https://tex.z-dn.net/?f=y-y_%20%7B0%7D%20%3D%20m%20%28x-x_%20%7B0%7D%29)
Where:
m: It's the slope
It is a point through which the line passes
In this case we have a line through:
(8,4) and (0,2)
Therefore, its slope is:
![m = \frac {2-4} {0-8} = \frac {-2} {- 8} = \frac {1} {4}](https://tex.z-dn.net/?f=m%20%3D%20%5Cfrac%20%7B2-4%7D%20%7B0-8%7D%20%3D%20%5Cfrac%20%7B-2%7D%20%7B-%208%7D%20%3D%20%5Cfrac%20%7B1%7D%20%7B4%7D)
Its point-slope equation is:
![y-4 = \frac {1} {4} (x-8)](https://tex.z-dn.net/?f=y-4%20%3D%20%5Cfrac%20%7B1%7D%20%7B4%7D%20%28x-8%29)
Then, we manipulate the expression to find the equation of the slope-intersection form:
![y-4 = \frac {1} {4} x- \frac {8} {4}\\y-4 = \frac {1} {4} x-2\\y = \frac {1} {4} x-2 + 4\\y = \frac {1} {4} x + 2](https://tex.z-dn.net/?f=y-4%20%3D%20%5Cfrac%20%7B1%7D%20%7B4%7D%20x-%20%5Cfrac%20%7B8%7D%20%7B4%7D%5C%5Cy-4%20%3D%20%5Cfrac%20%7B1%7D%20%7B4%7D%20x-2%5C%5Cy%20%3D%20%5Cfrac%20%7B1%7D%20%7B4%7D%20x-2%20%2B%204%5C%5Cy%20%3D%20%5Cfrac%20%7B1%7D%20%7B4%7D%20x%20%2B%202)
Therefore, the cut-off point with the y-axis is ![b = 2](https://tex.z-dn.net/?f=b%20%3D%202)
ANswer:
![y = \frac {1} {4} x + 2](https://tex.z-dn.net/?f=y%20%3D%20%5Cfrac%20%7B1%7D%20%7B4%7D%20x%20%2B%202)