<P> where p and q are the length of the diagonals . The length of the bimedian that connects the midpoints of the sides b and d is </P> <Dl> <Dd> n = 1 2 a 2 − b 2 + c 2 − d 2 + p 2 + q 2 . (\ displaystyle n = (\ tfrac (1) (2)) (\ sqrt (a ^ (2) - b ^ (2) + c ^ (2) - d ^ (2) + p ^ (2) + q ^ (2))).) </Dd> </Dl> <Dd> n = 1 2 a 2 − b 2 + c 2 − d 2 + p 2 + q 2 . (\ displaystyle n = (\ tfrac (1) (2)) (\ sqrt (a ^ (2) - b ^ (2) + c ^ (2) - d ^ (2) + p ^ (2) + q ^ (2))).) </Dd> <Dl> <Dd> p 2 + q 2 = 2 (m 2 + n 2). (\ displaystyle \ displaystyle p ^ (2) + q ^ (2) = 2 (m ^ (2) + n ^ (2)).) </Dd> </Dl>

Do all irregular quadrilaterals have no right angles