The algebraic expressions in this problem set are in the form of 6(3x + 4). The 6 is a factor and the (3x + 4) is a factor with 2 parts or "terms". The factor on the outside of the parentheses needs to be multiplied by each part of the other factor, so the 6 will be 'distributed' to each of the 2 parts of (3x + 4).
4(5x + 2) = 4 * 5x + 4 * 2 = 20x + 8 Easy!
5(3x + 7) = 5 * 3x + 5 * 7 = 15x + 35 Easy!
8(4x + 9) = 8 * 4x + 8 * 9 = 32x + 72 Easy!
Use the distributive property to multiply each algebraic expression. Strive to be able to accomplish the problems with ease and then strive for increasing your speed. Good luck and enjoy the challenge!