"Solving an equation" means finding the value of the variable that makes the equation true. You can observe what is happening in the equation and then "undo" it by using the opposite operation. Multiplication and division are opposite operations.
x/4 = 21 1st method: "Undo" the division. (x/4) * 4 = 21 * 4 which becomes x = 84. 2nd method: "What number can get divided by 4 and the result is 21?" The number 84 can get divided by 4 so the result is 21, so x = 84.
7x = 63 1st method: "Undo" the multiplication. (7x)/7 = 63/7 which becomes x = 9. 2nd method: "What number can get multiplied by 7 and the result is 63?" The answer is x = 9.
For each problem in this problem set you will need to solve the equations by either method. It is helpful to be able to use either method. Strive for being able to accomplish the problems with ease and then strive to increase your speed. Good luck and enjoy the challenge!