+238 abcd is a parallelogram ac is diagnol ,so it divides into 2 triangles?so prove that areas of 2 triangles are equal??and diagnols of parallelogram are equal or not??
+129899 Look at the following, matsunnymat :
To prove that AC divides the parallelogram into two equal parts.......note that, by the defintion of parallelogram, angle (ABC) = angle (CDA) ...... and AD = BC and AB = DC
Therefore, by SAS, triangle CDA = triangle ABC.....and if two triangles are equal [congruent, in this case ], their areas are also equal
In general......the diagonals of a parallelogram are not equal [except for squares and rectangles ]
For example.....the diagonal drawn from D to B above has a length of about 8.25....but the diagonal drawn from A to C has a length of only about 2.82
