2道英语数学题
1.ABCD is a rhombus where A=(-3,0),B=(0,4),C=(5,4) and D=(2,0) Prove that the diagonals are perpendicular bisectors of on another.
2.Prove that the point (-1,2genhao2),(genhao3,-genhao6)and (-genhao5,2) all lie on a circle with centre the origin.what are the radius and equation of the circle?