For a certain commodity the supply equation is given by S=2p+5

At a price of $1,there is a demand for 19units of the commodity.If the demand equation is linear and the market price is $3,find the demand equation?

To find the demand equation, we need to use the information given.

We know that at a price of $1, there is a demand for 19 units. This information tells us that the point (1, 19) lies on the demand equation.

To find the demand equation, we need to determine the slope and the y-intercept. The slope represents the relationship between the price and the quantity demanded, while the y-intercept represents the quantity demanded when the price is zero.

Let's calculate the slope first. We know that the market price is $3, and we are given a point on the demand equation, (1, 19). The slope can be calculated using the formula:

slope = (change in y)/(change in x)

In this case, the change in y is 19 - 0 = 19, and the change in x is 1 - 0 = 1. Therefore, the slope is 19/1 = 19.

Now, let's find the y-intercept. We can use the point (1, 19) to determine this. The y-intercept can be calculated using the formula:

y-intercept = y - (slope * x)

Using the point (1, 19), the slope of 19, and setting x = 1, the y-intercept can be calculated as follows:

y-intercept = 19 - (19 * 1) = 19 - 19 = 0

So, the y-intercept is 0.

Therefore, the demand equation is given by:

D = 19p + 0

Simplifying the equation, we get:

D = 19p

Hence, the demand equation for the commodity is D = 19p.

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