# How do you write the equation in point slope form given m=-3 and point (12,5)?

Jan 9, 2017

Start with the point-slope form $y = m x + b$. m becomes -3. use y = 5 and x = 12 to solve for b. Report the equation with m = -3 and the value of b.

#### Explanation:

$y = m x + b \text{ [1]}$

We are given that $m = - 3$:

$y = - 3 x + b \text{ [2]}$

We are given the point $\left(12 , 5\right)$, therefore, we may substitute y for 5 and 12 for x, into equation [2], then solve for the value of b:

$5 = - 3 \left(12\right) + b$

$b = 41$

The desired equation is:

$y = - 3 x + 41$