Given:
The figure of a right triangle.
To find:
The length of AB.
Solution:
In a right angle triangle,
[tex]\cos \theta=\dfrac{Base}{Hypotenuse}[/tex]
Using this trigonometric ratio for the given triangle, we get
[tex]\cos A=\dfrac{AB}{AC}[/tex]
[tex]\cos (60^\circ)=\dfrac{AB}{10}[/tex]
[tex]\dfrac{1}{2}=\dfrac{AB}{10}[/tex]
[tex]\dfrac{1}{2}\times 10=AB[/tex]
[tex]5=AB[/tex]
Therefore, the length of AB is 5 units.