Which of the following word problems can be solved using the equation 4(x + 8) = 40? a. A student has four bags of marbles. Each bag originally has x marbles. After taking out 8 marbles from each bag, there is a total of 40 marbles in the bags. How many marbles were originally in each bag?
b. Four friends share a box of cookies. After each friend receives x cookies, there are still 8 cookies left in the box. If there were initially 40 cookies in the box, how many cookies did each friend receive?
c. Oscar has 8 stacks of trading cards. Each stack originally has x trading cards. He adds 4 cards to each stack giving him a total of 40 trading cards. How many trading cards did Oscar originally have?
d. A square has a side length of x inches. Each side of the square will be increased by 8 inches to create a larger square. If the larger square has a perimeter of 40 inches, what is the side length, in inches, of the original square?