Question

What is the equation of a line that passes through the points (3,1 and (4,8)

Answer 1

$\frac{y - 1}{x - 3} = \frac{8 - 1}{4 - 3} \\ \frac{y - 1}{x - 3} = \frac{7}{1} \\ y - 1 = 7(x - 3) \\ y - 1 = 7x - 21 \\ 7x - y - 20 = 0$