If secA + tanA = 5, then sinA is equal to:
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Correct answer: D
Explanation
The correct answer is option 4 i.e. .
⇒ secA + tanA = 5 ------------------(1)
⇒ secA - tanA = 1/5 ------------------(2)
Add equation 1 and equation 2
⇒ secA + tanA = 5
⇒ secA - tanA = 1/5
⇒ 2sec A = 26/5
⇒ sec A = 13/5 = h/b
Hence
p =
⇒ p =
⇒ p =
⇒ p = = 12
And sin A = p/h = 12/13