Page 165 - ABCTE Study Guide_Neat

Question

Which answer choice shows the expression correctly simplified?

5(3c + 5d) – 2d

A 15c + 23d

B 15c + 25d

C 15c + 3d

D 15c + 27d

Answer

The correct answer is A. First distribute the 5 to the (3c + 5d), which gives you 15c + 25d (choice B). Then
subtract 2d from 25d, which leaves 23d. The answer is 15c + 23d.

Review

• Numbers are grouped into sets: whole numbers, integers, rational numbers, irrational
numbers, and real numbers.
• Number lines have a wide variety of purposes in many levels of mathematics.
• Math properties:

Commutative: order of numbers is not important when adding or multiplying

Associative: grouping of numbers is not important when adding or multiplying

Identity: for addition, adding zero keeps the number the same; for multiplication, multiplying
by one keeps the number the same

Multiplicative Property of Zero: anything times zero is zero

Distributive: combines addition/subtraction and multiplication for expanding expressions with
parentheses; a(b + c) = ab + ac

Numbers in Their Prime

Lesson Objective

In this lesson we will review prime and composite numbers. We'll also review some handy rules that make
division faster and easier.