What is theory of demand?
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Demand theory is an economic principle relating to the relationship between consumer demand for goods and services and their prices in the market. ... As more of a good or service is available, demand drops and so does the equilibrium price.

the formula for the equation of a circle is (x – h)2+ (y – k)2 = r2, where (h, k) represents the coordinates of the center of the circle, and r represents the radius of the circle. if a circle is tangent to the x-axis at (3,0), this means it touches the x-axis at that point.