Help with one and two ASAP please

For each proportion find the unknown number x 1/5/8=×/15

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.

True or false: the graph of y=f(bx) is a horizontal compression of the graph y=f(x) if b< 1