# How do you write the equation in slope intercept form given point (−1, 6) and has a slope of −3?

May 1, 2018

$y = - 3 x + 3$

#### Explanation:

If a straight line passes through $\left({x}_{1} , {y}_{1}\right)$ and has a slope $m$, then its equation can be written as $y - {y}_{1} = m \left(x - {x}_{1}\right)$.

By utilizing the values given in question, we get the equation,

$\rightarrow y - 6 = - 3 \left(x - \left(- 1\right)\right)$

$\rightarrow y - 6 = - 3 x - 3$

$\rightarrow y = - 3 x + 3$ which is of the form $y = m x + c$ (slope intercept form.

May 1, 2018

$y = - 3 x + 3$

#### Explanation:

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

•color(white)(x)y=mx+b

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

$\text{here } m = - 3$

$\Rightarrow y = - 3 x + b \leftarrow \textcolor{b l u e}{\text{is the partial equation}}$

$\text{to find b substitute "(-1,6)" into the partial equation}$

$6 = 3 + b \Rightarrow b = 6 - 3 = 3$

$\Rightarrow y = - 3 x + 3 \leftarrow \textcolor{red}{\text{in slope-intercept form}}$