In 4ABC, BC > AC. Using an indirect proof, prove that ∠A 6∼=
∠B

We are given:

a right angled triangle with the angle of elevation = 20 degrees

Hypotenuse of the Triangle = 500 m

Finding the change in Elevation:

We will use trigonometry in the given triangle to find the length of the perpendicular of the triangle

Using trigonometry, we found that the perpendicular = 500 * Sin 20 degrees

Perpendicular = 500 * 0.342           [sin(20 degrees) = 0.342]

Perpendicular = 171 m

The closest value to 171m in the given options is 170m

Therefore, 170m (option B) is correct