Both of these question please help me

Ben is three times as old as samantha, who is two years older than half of michel's age. if michel is 12. how old is ben?

In right ∆abc shown below, the midpoint of hypotenuse ac is located at d and segment bd is drawn. if ab = 12 and bc = 16, then explain why bd = 10. hint: consider what you know about the diagonals of a rectangle.

What is always true when two whole numbers are subtracted?