Step-by-step explanation:
A line can be repsented by slope-intercept form:
![y = mx + b](https://tex.z-dn.net/?f=y%20%3D%20mx%20%2B%20b)
where
is the slope of the line and
is the y-intercept.
The slope of the line is represented by the change in the
values on the line divided by the change in the
values on the line, or, simply put,
![\frac{y_{2} - y_{1}}{x_{2} - x_{1}}](https://tex.z-dn.net/?f=%5Cfrac%7By_%7B2%7D%20-%20y_%7B1%7D%7D%7Bx_%7B2%7D%20-%20x_%7B1%7D%7D)
for any two points
and
that are on the line.
Taking any two points on the given line, we can see that the slope of the above graph is
, so we can plug this in for
:
![y = x + b](https://tex.z-dn.net/?f=y%20%3D%20x%20%2B%20b)
This eliminates options C and D.
Now, the y-intercept is the point at which the line crosses the y-axis, or, simply put, what the value of the line is at
.
Looking at the line, it crosses the y-axis at
, meaning we can plug in
for
in our equation and get our answer:
![y = x + 6](https://tex.z-dn.net/?f=y%20%3D%20x%20%2B%206)