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: )

    = 3                                     (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

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

4 = 3 + b                               (Apply multiplicative identity property: )

                   (Subtract 3 from each side)

                   (Apply commutative property of addition: a + b = b + a) \ \

                              (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 = (3)(x) + 1                           (Substitute 3 for m and 1 for b)

y = 3x + 1                                (Simplify)

 The equation of the line that passes through the point (1, 4) and (2, 7) is

y = 3x + 1.