M19 | Maths Made Easy


Question: Find the length of the side marked z (2 d.p.)


Answer: Here we’re dealing with the opposite and adjacent sides, so we need a formula with both of those in. This means we’ll have to use \tan(x)=\frac{O}{A}.

First we rearrange the formula: we’re after the adjacent so we want to make A the subject.

A\times \tan(x)=O


Now we’ve made A the subject, we just need to plug in the values given.

z=\dfrac{3.6}{\tan(52)}=2.81km (2 d.p.)