Question

A line makes an angle of ${90}^{\circ }$ with the positive direction of the x-axis. The slope of the line is _____.

• A. $\frac{1}{\sqrt{2}}$
• B. 1
• C. $\frac{1}{\sqrt{3}}$
• D. Cannot be determined

Answer 1

The correct option is D Cannot be determined

Given, $\theta ={90}^{\circ }$
$\text{Slope}=\frac{y_2-y_1}{x_2-x_1}$
Since, line is making an angle $\theta ={90}^{\circ }$, it will be parallel to y-axis. Hence for such a line it's $x$ coordinate will always be equal.
$x_2-x_1=0$
$\therefore$ value of slope can not be determined.