Respuesta :

Answer:

A

Step-by-step explanation:

1. Plug in the numbers: 3 (3+5) = 3+21

2. Use PEMDAS (Order of Operations) to solve:

3 (8) = 24

24 = 24.

Answer:

A. 3

Step-by-step explanation:

3(x+5)=x+21

3x+15=x+21

3x=x+6

2x=6

x=3