Mathematics 4024 · O Level · Similarity

Similarity — practice question

The diagram shows that $ACD$ and $BCE$ are straight lines, with $AB$ parallel to $ED$.

(a)[3]

Prove that triangle $ABC$ is similar to triangle $DEC$. Give a reason for each statement you make.

(b)[2]

$AB = 6\,\text{cm}$ and $ED = 2\,\text{cm}$. The area of triangle $ABC$ is $45\,\text{cm}^2$. Calculate the area of triangle $DEC$.

Worked solution & mark scheme

This 5-mark question has a full step-by-step worked solution and mark scheme. One marking point: “Therefore, $\angle ACB=\angle ECD$.” …