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

done {{ upvoteCount }} Upvotes
clear {{ downvoteCount * -1 }} Downvotes
Eric Nicholas K
Eric Nicholas K's answer
3855 answers (Tutor Details)
For part i, note that "BD bisects AC at M" implies that AM = CM, or M is the midpoint of AC.

We use this fact AND the fact that BD is perpendicular to AC to help us find the equation of BD.

For part ii, the x-intercept can be found by setting y = 0.

For part iii, we use the fact that M is the midpoint of BD since ABCD is a parallelogram.