18 - 2,3,6,8
24 - 2,4,6,8,12
HCF = 8
As the question say this problem is a practice of the law of cosines!
The law of cosine: c^2=a^2+b^2-2ab*cos*c for any side a, b and c
The law can also be written as c=sqrt(a^2+b^2-2abcosc)
Now use this formula!(note cos 100 degrees is about 0.8623)
c=sqrt(15^2+16^2-2*15*16*cos100)
solving this we can MN is about 23.75
Round this to the nearest tenths now!
We get 23.8!
Thus the answer is D
Answer:

Step-by-step explanation:
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