Function that represent straight line

For any 2 point A(0,0) , B(${\displaystyle x_{o},y_{o}}$) a straight line can be drawn . The slope of the line is

${\displaystyle m={\frac {y_{o}}{x_{o}}}}$

Therefore,

${\displaystyle y_{o}=mx_{o}}$

For a point C(${\displaystyle x,y}$) on the same line of the slope m

${\displaystyle m={\frac {y-y_{o}}{x-x_{o}}}}$

${\displaystyle y=y_{o}+m(x-x_{o})}$