Question

The slope of a line parallel to Y-axis is zero.

• A. True
• B. False

Answer 1

The correct option is B

False

The slope of a line passing through points $(x_1,y_1)$ and $(x_2,y_2)$ is $\frac{y_2-y_1}{x_2-x_1}$.

Given the line is parallel to Y-axis.

$⟹$ the points on the line has the same abscissa. I.e. $x_1=x_2$

Therefore, $x_2-x_1=0$.

I.e. the denominator of the expression $\frac{y_2-y_1}{x_2-x_1}$ is zero. Hence the slope of a line parallel to Y-axis cannot be determined.