Answer:
Cos B = 4/5
Explanation:
From the question given above, the following data were obtained:
Sine B = 3/5
Cos B =?
Recall:
Sine B = Opposite / Hypothenus
Sine B = 3/5
Therefore,
Opposite = 3
Hypothenus = 5
Next, we shall determine the Adjacent. This can be obtained as follow:
Opposite = 3
Hypothenus = 5
Adjacent =?
Hypo² = Adj² + Opp²
5² = Adj² + 3²
25 = Adj² + 9
Collect like terms
Adj² = 25 – 9
Adj² = 16
Take the square root of both side
Adj = √16
Adjacent = 4
Finally, we shall determine Cos B. This can be obtained as follow:
Hypothenus = 5
Adjacent = 4
Cos B =?
Cos B = Adjacent / Hypothenus
Cos B = 4/5