Eric Nicholas K's answer to Irah Athirah's Secondary 3 A Maths Singapore question.

done {{ upvoteCount }} Upvotes
clear {{ downvoteCount * -1 }} Downvotes
Eric Nicholas K
Eric Nicholas K's answer
5997 answers (Tutor Details)
1st
Good afternoon Irah! Here is what we can do for this question.

FIrstly, do not be afraid just because the question is an 11 mark question which is expected to be tedious. We just do the question normally.

To find the area, we need to use the shoelace method or the usual 1/2 x base x height method. Either way, we need to obtain the coordinates of C and E.

To find the coordinates of C, we just have to use the fact that D is the midpoint of BC.

Finding the coordinates of E is much harder. The only way we can do this is to realise that lines DE and CE meet at E, so we need to form the equations of DE and of CE, knowing that DE is parallel to AC and CE is perpendicular to DE.

Hopefully my workings help! Let me know if you need more explanation and I will do my best to explain them to you again!