How do you write an equation in point slope form given (3, 5); slope = -9?

Jul 24, 2016

The equation will be $y = - 9 x + 32$.

Explanation:

Since we know that the slope is $- 9$ we can write:
$y = - 9 x + b$

Then plugging in $\left(3 , 5\right)$ will let us solve for $b$.
$5 = - 9 \cdot 3 + b$
$5 + 27 = b$
$b = 32$

So the equation is:
$y = - 9 x + 32$