Y=(x+1)(x-1) this is factored out
Multiply the cost of an item or service by the sales tax in order to find out the total cost. The equation looks like this: Item or service cost x sales tax (in decimal form) = total sales tax. Add the total sales tax to the Item or service cost to get your total cost.
Make sure you put the sales tax into decimal form. You do this by taking the percentage and sliding the decimal point two places to the left:
7.5% sales tax becomes .075 in decimal form
3.4% sales tax becomes .034 in decimal form
5% sales tax becomes .05 in decimal form
Example: $60 (item cost) x .075 (sales tax) = $4.5 total sales tax
