Question

Find the slope of all the lines perpendicular to the line with slope $\frac{-1}{2}$.

• A. 2
• B. -2
• C. $\frac{1}{2}$
• D. $\frac{-1}{2}$

Answer 1

The correct option is A 2

$\underset{–}{ConceptInvolved:}$
Product of the slopes of perpendicular lines = -1.

$\underset{–}{Method:}$
Slope of the given line is $\frac{-1}{2}$.
Slope of all the lines perpendicular to the line with slope $\frac{-1}{2}$ will be given by
$=\frac{-1}{\frac{-1}{2}}$
$=-1÷\frac{-1}{2}=-1\times \frac{-2}{1}=2$

Also,
$\frac{-1}{2}\times 2=-1$