1 Glycerin, an ingredient in some toothpastes, can interfere with strengthening your teeth. 2  Glycerin layers your tooth in a sticky film that keeps the minerals in your saliva from interacting with your enamel to strengthen it.. Chew sugar-free gum. The gum promotes saliva production, without the sugar that makes weakened enamel worse. Gum with the natural sweetener xylitol doesn't feed the bacteria that weakens your enamel, and xylitol has actually been shown to strengthen tooth enamel.
Demand functions for a straight-line demand curve take the following form: Quantity = a - (b x Price). where a and b are constants that must be determined for each particular demand curve. When price changes, the result is a change in quantity demanded as one moves along the demand curve.
Shift in the Demand Curve. A shift in the demand curve occurs when the whole demand curve moves to the right or left. For example, an increase in income would mean people can afford to buy more widgets even at the same price.