What is the square root of -1?

Which of the following are accepted without proof in a logical system? check all that apply.

The distributive property allows you to say that 3(x − 1) = 3x −

Jada has a meal in a restaurant she adds up the prices listed on the menu for everything they ordered and gets a subtotal of $42.00. when the check comes, it says they also need to pay $3.99 in sales tax. what percentage of the subtotal is the sales tax