Write a coordinate proof of the following theorem: if a quadrilateral is a kite, then it’s diagonals are perpendicular

Each morning papa notes the birds feeding on his bird feeder. so far this month he has see. 59 blue jays, 68 black crows, 12 red robin's and 1 cardinal. what is the probability of a blue jay being the next bird papa sees

Rhombus adef is inscribed into a triangle abc so that they share angle a and the vertex e lies on the side bc . what is the length of the side of the rhombus if ab=c, and ac=b.

Factor and solve to find roots x squared -x - 90 =0