If sin (5x - 25°) = cos(5y + 25°), where 5x - 25° and 5y + 25° are acute angles, then the value of (x + y) is:
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Correct answer: C
Explanation
The correct answer is Option 3 i.e. 18°.
Given that:
sin (5x - 25°) = cos(5y + 25°), where 5x - 25° and 5y + 25° are acute angles,
Sinθ = cos (90°- 0)
As per the question,
⇒ sin (5x - 25°) = cos(5y + 25°)
⇒ sin (5x - 25°) = sin 90 - (5y + 25°)
⇒ (5x - 25°) = 90° - (5y + 25°)
⇒ 5x + 5y = 90°
⇒ x + y = 90°/5
⇒ x + y = 18°