Answer this and explain please
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Answer:
x = 3
Step-by-step explanation:
The sum of two interior angles in a triangle is equal to an exterior angle that's supplementary to the third interior angle:
15x + 5 + 22x + 4 = 120 add like terms
37x + 9 = 120 subtract 9 from both sides
37x = 111 divide both side by 37
x = 3 and to find the angles replace x with 3 in given expressions