Question

An architect drew a figure of window as shown in the figure. Provided with the information in the figure , find the value of $3\cos x$.

Answer 1

From the figure we have, 2 angles equal (both $x$).

So, the corresponding sides are also equal.

For isosceles triangle, the perpendicular bisector of base (the 3rd side) passes through vertex (where 2 equal sides meet).

So, $\cos x=\frac{16}{24}=\frac{2}{3}$

Hence, $3\cos x=3\times \frac{2}{3}=2$