Angles C and D are supplementary, or they add up to 180.
b = 180 - 75 - (180 - 127)
Hope this helps!
Is there more to this question?
Answer:

Step-by-step explanation:
Refer to the attached image.
A right triangle is considered so when one of its corners are 90°.
If sides a and b are equal in length, then the corners across from them are equal in size as well.
The only way for this to be possible is if both corners A and B(opposite of sides a and b) are 45°.
Pythagorean theorem
This theorem states that the square of a right triangle's long side is equal to the sum of the squares of the shorter sides.
In this case:

but since:

the equation can be solved by replacing a with b in the equation:

Are those your only choices?
The correct answer is: [A]: " 8 √3 " .
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Note:
√192 = √64 * √3 = 8 √3 ; which is: "Answer choice: [A] ."
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