Please help I need to turn this is 30 min.

Find the value of the cosine for angle a

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 are the solutions of the system? solve by graphing. y = x^2 + 3x + 2 y = 2x + 2