Answer:
Required angle measures 39°
Explanation:
Let's say, x measures the angle between the hypotenuse and the common base of two triangles.
Sin(x) = 5/8
x = 39°
This angle is complementary to the angle other than theta (let's say y) in the required triangle.
90 - x = y and 90 - theta = y
>>> Theta = x
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