Answers:
x = 51
y = 39
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Step-by-step explanation:
The angles 39 and x form a right angle, aka 90 degree angle. This is shown by the small square angle marker.
One equation to solve is x+39 = 90. Doing so leads to x = 51 after subtracting 39 from both sides.
Similarly, another equation to solve is x+y = 90. Plug in x = 51 and isolate y
x+y = 90
51+y = 90
y = 90-51
y = 39