Answer:
c
Step-by-step explanation:
For this case we must simplify the following expression:

We eliminate the parentheses taking into account that:

So, we have:

We add similar terms taking into account that:
Different signs are subtracted and the sign of the major is placed:

Answer:

Answer:
Step-by-step explanation:
B
Answer:
66 cm
Step-by-step explanation:
Diameter (d) = 21 cm
