Answer: Approximately 35.54 degrees
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Step-by-step explanation:
With respect to reference angle x, the 5 is the opposite side, and the adjacent side is 7 units long.
We'll use the tangent ratio here
tan(angle) = opposite/adjacent
tan(x) = 5/7
x = arctan(5/7)
x = 35.5376777919743 approximately
x = 35.54
I rounded to two decimal places, but you can round however you need to or however your teacher instructs. Arctangent is the same as inverse tangent. Be sure that your calculator is in degree mode.