Question

How do you find the slope of a straight line obtained on a graph?

Answer 1

Slope of a straight line :

1. The slope of a straight line graph gives the rate of change of quantity taken on the y-axis with the quantity taken on the x-axis.
2. The slope of a line gives the measure of its steepness and direction.
3. The slope of a straight line between two points says (x₁,y₁) and (x₂,y₂) can be easily determined by finding the difference between the coordinates of the points.
4. The slope is denoted by the letter m.
5. $m=\frac{⧍y}{⧍x}=\frac{y_2-y_1}{x_2-x_1}$

Steps to find the slope of a straight line obtained on a graph:

1. Take two points P and Q on the line such that they should not be close and should not touch endpoints.
2. These points should be chosen such that the values of x and y for these points can be read on the axes.
3. Draw horizontal and vertical lines from these points on axes.
4. Read the value of x (say x₁) and the value of y (say y₁) corresponding to point P and similarly the values of x and y for point Q.
5. Calculate,$⧍y=y_2-y_1$ and$⧍x=x_2-x_1$.
6. Calculate the slope of the graph as:

$m=\frac{⧍y}{⧍x}=\frac{y_2-y_1}{x_2-x_1}$