Question

Determine the measures of and to the nearest tenth of a degree, and the length of side

AB to one decimal place.

A B

C

3

4

D

A= C=

Side

AB=

Answer 1

Figure:

here,

$\cos62\degree=\dfrac{l(AB)}{12}\\\ \\\Rightarrow l(AB)=12\times \cos62\degree\\\Rightarrow AB=12\times 0.469 =5.63\ cm$

Hence, $\boxed{AB=6.6\ cm}$