PLS I NEED HELP ASAP 2 PART QUESTION

Two times a number plus three times another number equals 4. three times the first number plus four times the other number is 7. find the numbers

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. after tax the total is 45.99. what percentage of the subtotal is the total?

Find the missing factor. write your answer inexponential form.9^2=9^4×