Equilibrium quantity and equilibrium price

Question

The demand equation for the Bohen Industries Jigrods is 3x+p-1500=0, where x is the quantity of items demanded per week, and p is the unit price in dollars. The supply equation is 2x-3p+1200=0, where x is the quantity the supplier will make available when the unit price is p dollars.

 

Find the equilibrium quantity, and equilibrium price for the jigrods.

Answer 1

So you want to know when the supply and demand are equal. This is a normal system of equations and can be solved ny the substitution method or the elimination method. I'll use the substitution method. So solving the first equation for p, you'd get

p = -3x + 1500......substitut that in the second equation and get

 

2x - 3(-3x +1500) + 1200 = 0

2x + 9x - 4500 + 1200 = 0

11x  - 3300 = 0

11x = 3300

    x = 300

 

Substituting back into one of the equations

3(300) + p - 1500 = 0

p - 600 = 0

p = 600

 

Hope this helped.