Step 1: Calculate the angle γ in the triangle 'c'.
In the right-angled triangle 'c', the side adjacent to angle γ is 6, and the hypotenuse is 15. We use the cosine function.
cos(γ)=hypotenuseadjacent
cos(γ)=156
cos(γ)=0.4
To find γ, we take the inverse cosine:
γ=arccos(0.4)
γ≈66.4218∘
Rounding to the nearest 0.1 degree:
γ≈66.4∘
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