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 (Multiply: )
(Subtract 3 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 = (3)(x) + 1 (Substitute 3 for m and 1 for b)
\y = 3x + 1
\The equation of the line that passes through the point (1, 4) and (2, 7) is
\y = 3x + 1.