# [SPM Add Math Pahang(Kuantan) 2021 Paper 1 Q10 Surd] How to solve this question?

### Question

(b) Luas sebuah segitiga bersudut tegak ialah (-2+20 \sqrt 3) cm^2. Satu daripada sisinya mempunyai panjang (8-2\sqrt3)cm. Cari panjang sisi yang berserenjang dengannya dalam bentuk a+b\sqrt3.
The area of right-angled triangle is (-2+20 \sqrt 3) cm^2. One of its sides has length (8-2\sqrt3)cm. Find the length of the side perpendicular to it in the form a+b\sqrt3.

Hi Farhaini,
I think you made a careless mistake where you missed out the 2 in (8- 2\sqrt 3).

Also, I noticed that there is a typing error in the question where the BM version says a+b\sqrt3 but the BI version says +b\sqrt3. Most probably the BM version is the correct one.

Here is my working for your reference:

Hope this helps!

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Ohhh yahhh Thank you very much !

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