Equation of a line:
[tex]y=mx+c[/tex]
m = gradient: The difference between two y points and two x points.
[tex]m= \frac{\Delta y}{\Delta x} [/tex]
c = y-intercept: Where the line crosses the y-axis (x=0)
You have:
[tex]y=\textunderscore\textunderscore \ x + \textunderscore[/tex]
so you are missing the m and the c.
To calculate m find two y coordinates -you have (12, 7) and (0, 1)- and subtract them. Then divide this by the subtracted values of the x coordinates -you have (12, 7) and (0, 1)- This gives:
[tex]m= \frac{7-1}{12-0} [/tex]
[tex]m= \frac{6}{12} [/tex]
[tex]m=0.5[/tex]
To calculate the c, you just see where the line crosses the y-axis. Because you have the point (0, 1), you know that when x=0, y=1. Because x=0 is on the y-axis, you can tell that the line passes through y=1. This makes your c = 1:
[tex]c=1[/tex]
When you plug these values into the equation you get your answer:
[tex]y=0.5x+1[/tex]
