Max's T-shirt business uses the demand function [tex]P = -Q + 34[/tex] and the supply function [tex]P = Q - 10[/tex]. According to these functions, what will the equilibrium point be for Max's T-shirt business (i.e., the number of T-shirts sold and the price at which they're sold)?

A. [tex]\((10, 34)\)[/tex]

B. [tex]\((12, 22)\)[/tex]

C. [tex]\((34, 10)\)[/tex]

D. [tex]\((22, 12)\)[/tex]



Answer :

To find the equilibrium point for Max's T-shirt business, we need to determine the quantity of T-shirts sold (Q) and the price at which they are sold (P) at the point where the demand and supply functions intersect.

The demand function is given by:
[tex]\[ P = -Q + 34 \][/tex]

The supply function is given by:
[tex]\[ P = Q - 10 \][/tex]

At equilibrium, the quantity demanded equals the quantity supplied. Therefore, we set the two equations equal to each other:

[tex]\[ -Q + 34 = Q - 10 \][/tex]

Next, we solve for [tex]\(Q\)[/tex]:

1. Add [tex]\(Q\)[/tex] to both sides:
[tex]\[ 34 = 2Q - 10 \][/tex]

2. Add 10 to both sides:
[tex]\[ 44 = 2Q \][/tex]

3. Divide by 2:
[tex]\[ Q = 22 \][/tex]

Now that we have the equilibrium quantity, we substitute [tex]\(Q = 22\)[/tex] back into either the demand or supply function to find the equilibrium price [tex]\(P\)[/tex]. Using the supply function:

[tex]\[ P = Q - 10 \][/tex]
[tex]\[ P = 22 - 10 \][/tex]
[tex]\[ P = 12 \][/tex]

Therefore, the equilibrium point is [tex]\((22, 12)\)[/tex].

The correct answer is:
D. [tex]\((22, 12)\)[/tex]