Questions: Question number 5.
Right triangle ABC is given below. If AB = 4, find the area of this triangle.
None of the above
O 8√3
O 4√3
O 2√3
O √3
O 3
A
60°
B C
Transcript text: Question number 5.
Right triangle ABC is given below. If AB = 4, find the area of this triangle.
None of the above
O 8√3
O 4√3
O 2√3
O √3
O 3
A
60°
B C
Solution
Solution Steps
Step 1: Find AC
In the right triangle ABC, angle C is 90 degrees, and angle A is 60 degrees. Therefore, angle B is 30 degrees. We are given that AB = 4.
We can use the trigonometric ratio for the sine function in a 30-60-90 triangle.
\\( \sin(30^{\circ}) = \frac{AC}{AB} \\)
\\( \frac{1}{2} = \frac{AC}{4} \\)
\\( AC = 4 \times \frac{1}{2} = 2 \\)
Step 2: Find BC
We can use the trigonometric ratio for the cosine function in a 30-60-90 triangle.
\\( \cos(30^{\circ}) = \frac{BC}{AB} \\)
\\( \frac{\sqrt{3}}{2} = \frac{BC}{4} \\)
\\( BC = 4 \times \frac{\sqrt{3}}{2} = 2\sqrt{3} \\)
Step 3: Calculate the area
The area of triangle ABC is given by:
Area = \\( \frac{1}{2} \times \text{base} \times \text{height} \\)
In our case, the base is BC, and the height is AC.
Area = \\( \frac{1}{2} \times BC \times AC \\)
Area = \\( \frac{1}{2} \times 2\sqrt{3} \times 2 \\)
Area = \\( 2\sqrt{3} \\)