8n + 12 - 5n = 21

n=?

Step-by-step explanation:

hello:

8n + 12 - 5n = 21

8n + 12 - 5n-12 = 21 - 12

3n = 9

n = 9/3 = 3

n=3

Step-by-step explanation:

Simplifying

8n + 12 + - 5n = 21

Reorder the terms:

12 + 8n + - 5n = 21

Combine like terms: 8n + - 5n = 3n

12 + 3n = 21

Solving

12 + 3n = 21

Solving for variable 'n'.

Move all terms containing n to the left, all other terms to the right.

Add '-12' to each side of the equation.

12 + - 12 + 3n = 21 + - 12

Combine like terms: 12 + - 12 = 0

0 + 3n = 21 + - 12

3n = 21 + - 12

Combine like terms: 21 + - 12 = 9

3n = 9

Divide each side by '3'.

n = 3

Simplifying

n = 3