Page 5 - Algebra 1

Adding and Subtracting Algebraic Expressions
When adding or subtracting algebraic expression, you have to combine the like terms.
• Like terms
Like terms are terms with the same variable and the same exponent. It’s similar to adding oranges with oranges and not apples.
Worked Example 2
Find the sum of the following algebraic expression.
(5x – 12) + (4x + 3)
Solution:
Write the term without parenthesis
5x – 12 + 4x + 3
Combine the like terms. Here the like terms are constants and variables. The variables are 5x and 4x,
and the constants are – 12, and 3.
5x + 4x – 12 + 3
Now, add the like terms
9x – 9
REMEMBER:
When subtracting two algebraic expressions, distribute
–1, change the sign of each term.
Distributive Property in Algebraic Expression
The distributive property is p(q + r) = pq + pr
Using the distributive property, you can multiply a common factor to the terms of the algebraic expression.
For example,
6 (2x + 3)
Use the distributive property to multiply the common factor 6. 6(2x) + 6 (3)
12x + 18
–1 in the second parenthesis. When distributing
Worked Example 3
Use the distributive property to write an algebraic expression.
8(–2x – 1)
Solution:
Use the distributive property to multiply the common factor 6. 8(–2x) + 8 (–1)
–16x – 8
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ALGEBRA