Question

Find the distance from point C to point D.

Enter as a decimal rounded to the nearest tenth.
D
A
25°
C
555 m
CD = [?] m
B

Answer 1

Explanation:

CD = AB

the inner angle at C = 25° = the outer angle at A.

so, the inner angle at A = 90 - 25 = 65°

now we use the law of sine

a/sin(A) = b/sin(B) = c/sin(C)

with a, b, c being the triangle sides, and A, B, C the angles opposite of the correlated sides.

so, in our case

555/sin(65) = AB/sin(25) = CD/sin(25)

CD = 555×sin(25)/sin(65) = 258.8007503...

≈ 258.8 m