The first thing you should know is the gradient definition for a line.
The gradient of a straight line tells us how much inclination it has. Therefore, the gradient of a line represents the slope of the line.
We have then that the generic equation of the line is:
y-yo = m (x-xo)
Substituting the values:
y-3 = 3 (x-2)
Rewriting:
y-3 = 3x-6
y = 3x-6 + 3
y = 3x-3
y = 3 (x-1)
Answer:
The equation of the line is:
y = 3 (x-1)