Supply, Demand, and Market Equilibrium

In supply (and demand) problems, [tex]$N$[/tex] is the number of items the supplier will produce (or the public will buy) if the price of the item is [tex]$x$[/tex] dollars. For a particular product:

- The supply equation is: [tex]N = 3x + 511[/tex]
- The demand equation is: [tex]N = -2x + 676[/tex]

Supply and demand lines intersect at the equilibrium price. This is the price at which there is neither a surplus nor shortage in the market (supply and demand are equal). Solve this system of equations to determine the point at which the two lines intersect. Give your answer as an ordered pair.

The two lines intersect at the point: [tex]( \square, \square )[/tex]

In this situation, what is the selling price when supply and demand are in equilibrium?

When supply and demand are in equilibrium, the selling price per item is $ [tex]\square[/tex].

What is the number of items in the market when supply and demand are in equilibrium?

There are [tex]\square[/tex] items in the market when supply and demand are in equilibrium.

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Answer :

To determine the equilibrium point where supply and demand are equal, we need to solve the system of equations given by the supply and demand equations. Specifically, we need to find the value of [tex]\( x \)[/tex] (price) where the number of items supplied equals the number of items demanded ([tex]\( N \)[/tex]).

The equations provided are:

1. Supply equation: [tex]\( N = 3x + 511 \)[/tex]
2. Demand equation: [tex]\( N = -2x + 676 \)[/tex]

At the equilibrium point, the supply equals the demand. Therefore:

[tex]\[ 3x + 511 = -2x + 676 \][/tex]

We'll solve for [tex]\( x \)[/tex] step by step:

1. Combine the terms involving [tex]\( x \)[/tex] and the constant terms:
[tex]\[ 3x + 2x = 676 - 511 \][/tex]

2. Simplify the equation:
[tex]\[ 5x = 165 \][/tex]

3. Solve for [tex]\( x \)[/tex]:
[tex]\[ x = \frac{165}{5} \][/tex]
[tex]\[ x = 33 \][/tex]

Now that we have the equilibrium price [tex]\( x \)[/tex], we substitute this value back into either the supply or demand equation to find the equilibrium quantity [tex]\( N \)[/tex].

Using the supply equation [tex]\( N = 3x + 511 \)[/tex]:

[tex]\[ N = 3(33) + 511 \][/tex]
[tex]\[ N = 99 + 511 \][/tex]
[tex]\[ N = 610 \][/tex]

So, the equilibrium price (selling price) when supply and demand are in equilibrium is [tex]\( x = 33 \)[/tex] dollars, and the number of items in the market is [tex]\( N = 610 \)[/tex].

To summarize:

1. The two lines intersect at the point: [tex]\((33, 610)\)[/tex].
2. The selling price per item when supply and demand are in equilibrium is [tex]\(\$ 33\)[/tex].
3. There are 610 items in the market when supply and demand are in equilibrium.