Why isn't price a factor in influencing a left or right shift in the demand curve? what does it mean when there is a shift to the right?

Your answer is: Changes in production cost and related factors can cause an entire supply curve to shift right or left. This causes a higher or lower quantity to be supplied at a given price. A demand curve or a supply curve is a relationship between two, and only two, variables: quantity on the horizontal axis and price on the vertical axis. The assumption behind a demand curve or a supply curve is that no relevant economic factors, other than the product’s price, are changing.

Changes in production cost and related factors can cause an entire supply curve to shift right or left. This causes a higher or lower quantity to be supplied at a given price. The ceteris paribus assumption: Supply curves relate prices and quantities supplied assuming no other factors change.

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