How do you find the line that passes through the point (-1, 1) and has slope 2?

Oct 27, 2017

$y = 2 x + 3$

Explanation:

$\text{the equation of a line in "color(blue)"slope-intercept form}$ is.

$\textcolor{red}{\overline{\underline{| \textcolor{w h i t e}{\frac{2}{2}} \textcolor{b l a c k}{y = m x + b} \textcolor{w h i t e}{\frac{2}{2}} |}}}$

$\text{where m is the slope and b the y-intercept}$

$\text{here } m = 2$

$\Rightarrow y = 2 x + b \leftarrow \text{ is the partial equation}$

$\text{to find b substitute "(-1,1)" into the partial equation}$

$1 = - 2 + b \Rightarrow b = 3$

$\Rightarrow y = 2 x + 3 \leftarrow \textcolor{red}{\text{in slope-intercept form}}$
graph{2x+3 [-10, 10, -5, 5]}