How do you substitute the equations x+4y=14 and 3x+4y=22

Alicia puts $400 in a bank account. each year the account earns 5% simple interest. how much money will be in her bank account in six months?

One side of a rectangle is 7 centimeters shorter than six times the other side. find the length of the longer side if we also know that the perimeter of the rectangle is 266 centimeters.

Dana wants to identify the favorite professional baseball team of people in her community. she stands outside a local sporting goods store and asks every other person who enters, "what is your favorite professional baseball team? " will the results of her survey be valid? explain.