Point slope form is:
y − y[tex]_{1} [/tex] = m(x − x[tex]_{1} [/tex])
Where x[tex]_{1} [/tex] and y[tex]_{1} [/tex] are two known coordinates and m is the slope.
Substitute (4,2) as x and y and 3 as m to find the point-slope form.
y − 2 = 3(x − 4)
Taking it to the next step would be to turn this into slope-intercept form, y=mx+b
y − 2 = 3(x − 4)
y − 2 = 3x − 12
y = 3x − 10