Sally and mabel had the same number of cards at first. after sally sold 18 of her cards, mabel had four times as many cards as sally. how many cardsdid each girl have at first?

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.

In angle pqr find the measure of

The table shown below gives the approximate enrollment at the university of michigan every fifty years. how many more students were enrolled at the university of michigan in 1950 than in 1900?