# How do you find the slope of a line perpendicular to the line passing through the given two points (0, 0) and (2, -9)?

Apr 13, 2018

color(violet)("Slope of perpendicular line "m_p = -1 / m = 9/2

#### Explanation:

Slope of the given line $m = \frac{{y}_{2} - {y}_{1}}{{x}_{2} - {x}_{1}}$

$\left({x}_{1} , {y}_{1}\right) = \left(0 , 0\right) , \left({x}_{2} , {y}_{2}\right) = \left(2 , - 9\right)$

$m = \frac{- 9 - 0}{2 - 0} = - \frac{9}{2}$

Slope of perpendicular line ${m}_{p} = - \frac{1}{m} = - \frac{1}{- \frac{2}{9}} = \frac{9}{2}$