PLEASE HELP MEEE with math...

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.

Evaluate 3(a + b + c)squared for a = 2, b = 3, and c = 4. a. 54 b. 243 c.729 add solution .

Can someone me with #s 8, 9, and 11. with just one of the three also works. prove using only trig identities.