Question

Write the slope-intercept form of the equation of the line which passes through the points (1, 6) and (2, 9

Answer 1

Start with the slope formula.

\[m=\frac{ y_{2}-y_{1} }{ x_{2}-x_{1} }\]

Plug in y2=9, y1=6, x2=2 and x1=1

\[m=\frac{ 9-6 }{ 2-1 }\]

\[m=3\]

So the slope of the line that goes through the points (1, 6) and (2, 9) is m=3

Now let's use the point slope formula:

Start with the point slope formula

\[y-y _{1}=m(x-x _{1})\]

Plug in m=3, x1=1 and y1=6

\[y-6=3(x-1)\]

\[y-6=3x-3\]

\[y=3x-3+6\]

\[y=3x+3\]