Question

At a unit price of $360, the quantity demanded of a certain commodity is 76 pounds. If the unit price increases to $470, the quantity demanded decreases by 11 pounds. Find the demand equation (assuming it is linear) where p is the unit price and x is the quantity demanded for this commodity in pounds.4

Answer 1

Answer:

P= -1.69 Q +488.4

Explanation:

x1= 76 y1= $360

x2= 11   y2= $470

x: quantity demanded

y: unit price

If we have two X values and two Y values, we can calculate the slope (m) of the equation by using this formula:

m= (y2-y1)/(x2-x1)

m=(470-360)/ (11-76)

m= -1.69

To find the equation we must use this formula:

Y-y1= m (X-x1)

We can use either of the points the problem gives.

Y-360= -1.69 (X-76)

Y-360= -1.69 X + 128.4

Y= -1.69 X+ 128.4+360

Y= -1.69 X +488.4

Price= -1.69 Quantity demanded +488.4