Answer:
Step-by-step explanation:
The slope-intercept form of an equation of a line:
[tex]y=mx+b[/tex]
m - slope
b - y-intercept
If a y-intercept is below origin, then b = 0. Therefore we have the equation:
[tex]y=mx[/tex]
Put the coordinates of the point (1, 2) to the equation:
[tex]2=1m\to m=2[/tex]
Therefore:
[tex]y=2x[/tex]