Given:
The figure of a right angle triangle.
To find:
The measure of side AB.
Solution:
In a right angle triangle,
[tex]\cos \theta=\dfrac{Adjacent}{Hypotenuse}[/tex]
In the given triangle,
[tex]\cos B=\dfrac{BC}{AB}[/tex]
[tex]\cos (20^\circ)=\dfrac{7}{AB}[/tex]
[tex]\cos (20^\circ)AB=7[/tex]
[tex]AB=\dfrac{7}{\cos (20^\circ)}[/tex]
On further simplification, we get
[tex]AB=\dfrac{7}{0.93969}[/tex]
[tex]AB=7.449265[/tex]
[tex]AB\approx 7.45[/tex]
Therefore, the measure of AB is 7.45 units.
