A binomial expression is one that has two terms, such as 3a - 1
When we add and subtract binomials, we combine the letter terms and the numbers separately.
Be careful with - signs and try to put the letter term first
(i.e. 3a -1 rather than -1 + 3a).
Example 1
Simplify
(3a - 1) + (2a + 7)
Answer
(3a - 1) + (2a + 7)
= 3a - 1 + 2a + 7
= 3a + 2a - 1 + 7
= 5a + 6
Example 2
Simplify
(3a - 1) - (2a + 7)
Answer
(3a - 1) - (2a + 7)
= 3a - 1 - 2a - 7
= 3a - 2a - 1 - 7
= a - 8
Example 3
Simplify
(3a - 1) - (2a - 7)
Answer
(3a - 1) - (2a - 7)
= 3a - 1 - 2a + 7
= 3a - 2a - 1 + 7
= a + 6
