Use angle sum property (the 3 angles in a triangle sum up to 180°).
2x + x + 54 = 180
3x + 54 = 180
3x = 180 - 54
3x = 126
x = 126/3
x = 42
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Hope it helps ⚜
D: 89 is the prime number.
6/8a+4,6-2/4a. I think that this is the answer.
Permutation:
5! = 5 * 4 * 3 * 2 * 1 = 120
