Well, 4*16 is 64, so the rectangle and the square have an area of 64. We know that all sides of a square are equal, so they have to be the same number. Well, 8*8 is 64, right? So the length of each side of the square has to be 8 units. Hope this helped!
Let h be hamburgers and c be cheeseburgers. We know that We also know that This gives us a system of equations we can solve. My preferred method to solve systems is substitution, where we solve one equation for one of the variables, then substitute that solution in the other equation, reducing it to a single variable equation. One of the equations already equals h, so we can go straight into the sub part. Finally, we go back to the other equation and solve for h. So, total there were 253 cheeseburgers sold, and 325 hamburgers sold.