Question

Solve for a side in right triangles

I don’t know how to do this so please someone teach me how to do this?? I need help here!

Answer 1

Since you need to find the side length AC, you already have a 25° angle plus the right angle which indicates it 90°. With that you add them up to get 115°. Since the total of the triangle is 180° you subtract that to get 65°. to check the answer you add the degrees all together to make sure you have a total of 180°. Let me know if you need more clarification

Answer 2

2.33

Explanation:

imagine a circle. its center is A, and it goes through B, so its radius is AB.

then it is important to know that the sum of all the angles in a triangle is 180 degrees.

one angle (at C) is 90. the angle at B is 25. so, the angle at A is 180 - 90 - 25 = 65 degrees.

more back to our circle.

in this circle the line CB is the sine of the angle at A multiplied by the radius.

and AC is the cosine of the angle at A multiplied by the radius.

we can ignore the orientation + and - of these functions, as we are only interested in the absolute length (and we can mirror the triangle, and all the angles and side lengths still stay the same).

=> CB = sin(A)×AB

AC = cos(A)×AB

=> 5 = sin(65)×AB

=> AB = 5 / sin(65)

=> AC = cos(65)×5/sin(65) = 5 × (cos(65)/sin(65)) =

= 5 × cot(65) = 2.33