# What is the slope of the line perpendicular to  y=8/11x-4 ?

Nov 29, 2015

$- \frac{11}{8}$

#### Explanation:

Let ${a}_{1}$ be the slope of this line.
${a}_{1} = \frac{8}{11}$.

Let ${a}_{2}$ be the slope of the line perpendicular to line.

Then, ${a}_{1} {a}_{2} = - 1$. (this is a property of the slopes of perpendicular lines you need to know, that is, multiplying the slopes of two perpendicular lines should always give you -1).

i.e. $\frac{8}{11} {a}_{2} = - 1$

i.e. ${a}_{2} = - \frac{11}{8}$

That's it.