Question

How do you find the slope of a demand curve ?

Answer 1

Hint: Slope is represented by ‘ m ’ . The slope can be calculated by finding the ratio of the “ vertical change ” we say graphically as the y-axis denoted by $△y$ = $y_2-y_1$ , to the “ horizontal change “ we say graphically as the x-axis denoted by $△x$ = $x_2-x_1$ , between the two different points on a same line . The formula of slope is $m={\displaystyle \frac{y_2-y_1}{x_2-x_1}}.$ The demand curve is a graphical representation of the relationship between the price of a good or service and the quantity demanded for a given period of time . The price is drawn along the y-axis and the quantity demanded on the x-axis .

Complete step-by-step answer:
It is very easy to find the slope of a demand curve if you know the concept of basic slope . As per finding the slope , we must divide the rise by run .
If we talk about a demand curve then that means there will be a ratio of the change in price ( that is $△y$ = $y_2-y_1$ ) to the change in quantity demanded ( $△x$ = $x_2-x_1$ ) .
Let's consider change in price as $△P$ = $P_2-P_1$ .
Let's assume the change in quantity demanded as $△Q$ = $Q_2-Q_1$ .
Slope of Demand Curve = ${\displaystyle \frac{P_2-P_1}{Q_2-Q_1}}$ = ${\displaystyle \frac{△P}{△Q}}$ .
Hence , by this you can find the slope of a demand curve .
So, the correct answer is “ ${\displaystyle \frac{P_2-P_1}{Q_2-Q_1}}$ = ${\displaystyle \frac{△P}{△Q}}$ .”.

Note: In order to find this slope , we need to take two different points but it has to be on the demand curve .
The ratio of ordered pairs must be fulfilled .
Remember that this phenomenon works only when there will be a linear demand curve .
Need to learn derivatives , as the slope is the derivative at the specific quantity value.