You can put this solution on YOUR website! Need to draw it.
Law of Cosines
g^2=h^2+i^2-2hi cos G
g^2=64+144-2*8*12*(-.1045)
without rounding, making sure the last term will be positive, g^2=228.064 and g=15.1018
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Now use that for angle I.
i^2=g^2+h^2-2gh cos I
144=228.064+64-2(15.1018)(8)(cos I)
144=292.064-2(15.1018)(8)(cos I)
-148.064/-241.6288=0.61277
arc cos (0.61277)=52.2 degrees. ANSWER
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Check doing third angle
h^2=g^2+i^2-2gicos H
64=228.064+144-2(15.1018)(12)cos H
-308.064=-362.4432 cos H
angle H is 31.8 degrees (arc cos of 0.8500)
These add up to 180 degrees
