Explanation: When solving an equation, the goal is to isolate the variable (X). In order to do so, you must move everything else on the same side of the equation to the other side. So, in the equation 4=3+x, 3 is on the same side of the equation as X, so you must move it to the other side. When moving a number from one side of an equation to the other, you change the operation to the opposite: “+” becomes “-“, multiplication becomes division. Since the 3 in your equation is positive (+3), when you move it to the other side, it becomes “-3”. Thus: 4-3=x 1=x or x=1
The books are $5, and the magazines are $10. I’m not sure which way you want it explained but since magazines are twice the price of books, you can solve the equation 3b + 2b = 25. This gives you b=5 which you just multiply by 2 giving you the price of a magazine.
