The line equation in slope-intercept form is y = mx + b, where m is the slope and b

is the y-intercept.

First find the slope

m = 

    =                                (Substitute )

    =                                      (Subtract: )

    = 7                                        (Divide: )

Next find the y-intercept

Substitute the slope and the coordinates of the given point in slope-intercept form

line equation.

y = mx + b

2 = (7)(3) + b                        (Substitute 3 for m, 1 for x, and 4 for y)

2 = 21 + b                              (Multiply: )

             (Subtract 21 from each side)

                              (Additive inverse property:  )

                                (Subtract:  )

Finally write the equation of the line

Substitute the values of slope ‘m’ and y-intercept ‘b’ in slope intercept form

y = mx + b

y = (7)(x) + (19)                (Substitute 7 for m and –19 for b)

y = 7x 19                          (Product of two different signs is negative)

The equation of the line that passes through the point (3, 2) and (4, 9) is

y = 7x 19.