Question

Select all angles that have a cosine of 3/5.

Answer 1

Step-by-step explanation:

Given

Two similar triangles i.e. $\trianle ABC \ \text{and}\ \triangle A'B'C'$

from the figure, In $\triangle ABC$

$\Rightarrow \cos \alpha=\dfrac{AC}{AB}=\dfrac{3}{5}$

Also, In $\triangle A'B'C'$

$\Rightarrow \cos \alpha =\dfrac{A'C'}{A'B'}=\dfrac{6}{10}=\dfrac{3}{5}$