Question

Please help with this right triangle problem

Answer 1

Given:

The figure of a right angle triangle.

To find:

The measure of side AB.

Solution:

In a right angle triangle,

`\cos \theta=(Adjacent)/(Hypotenuse)`

In the given triangle,

`\cos B=(BC)/(AB)`

`\cos (20^\circ)=(7)/(AB)`

`\cos (20^\circ)AB=7`

`AB=(7)/(\cos (20^\circ))`

On further simplification, we get

`AB=(7)/(0.93969)`

`AB=7.449265`

`AB\approx 7.45`

Therefore, the measure of AB is 7.45 units.