Mistakes

When student answer the question mathematic especially subtopic coordination,they always do mistakes when  answer the question.some of the mistakes that students do is :

Example 1:

The diagram above show points E, F and H on a Cartesian plane.  If the midpoint of FH  and EG is the same point, find the coordinates of G.

mistake 1


Join point E to the midpoint of FH.  Extrapolate the straight line until it is of equal length to      the line joining point E and the midpoint.  Point G is the point where the line ends.

Therefore, the coordinates of point G is (4, 3)

Example 2

 Diagram above shows points marked on a grid of equal squares with sides 1 unit.  Which of  the point A, B, C or D, is 5 units from point T.

mistake

Solution
Distance of D from T