Answer: x = 12.176 (approximate)
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Angle 2 and angle 4 are adjacent angles and they also form a straight line, so this means they add to 180 degrees
(angle2)+(angle4) = 180
(13x)+(4x-27) = 180
(13x+4x)-27 = 180
17x-27 = 180
17x-27+27 = 180+27 ... add 27 to both sides
17x = 207
17x/17 = 207/17 .... divide both sides by 27
x = 12.176
