You can put this solution on YOUR website! Complementary angle for 53 degrees 12' :: 90-53 12' = 89 60' - 53 12' = 36 48'
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Supplementary angle for 121 degrees 47'38":: 180-47' 38" = 179 59' 60" -47' 38"
= 179 12' 22"
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Cheers,
Stan H.