Question

What is the equation of a line that passes through the points (1, 2) and (4, 8) in point-slope form?

Answer 1

First let us find the slope m of the line, we have

`\begin{gathered} m=(8-2)/(4-1) \\ m=(6)/(3) \\ m=2 \end{gathered}`

Equation of a line in point-slope is given as

`\begin{gathered} y-y_1=m(x-x_1) \\ using\text{ the point \lparen1, 2\rparen we have } \\ y-2=2(x-1) \\ y-2=2x-2 \\ y=2x-2+2 \\ y=2x \end{gathered}`

Hence the answer is y = 2x