Use inverse operation to solve 116=4n

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

Sally deposited money into a savings account paying 4% simple interest per year. the first year, she earned $75 in interest. how much interest will she earn during the following year?

The equation for two lines in the coordinate plane are 2dx+y=4 and -6x+y=3, where d represents an unknown value. what value(s) of d would make these lines parallel?