Respuesta :

Answer:

12a + 6b

Step-by-step explanation:

Combine like terms

12a+7b-b

Combine like terms

12a+6b

Hence, 12a+6b = 3a+9a+7b-b

[RevyBreeze]

ANSWER: ⇒ 12a + 6b

Simplify or expand:

3a + 9a + 7b - b

Reorder and gather like terms:

(3a + 9a) + (7b - b)

Collect coefficients of like terms:

(3 + 9) × a + (7 - 1) × b

Calculate the sum or difference:

12a + (7 - 1) × b

Calculate the sum or difference:

12a + 6b