Hey Madoudou!
For the first picture, the correct answer is option B
They say that AB = BC = CD and they want us to find JM.
Well, since the right side are equal, the left side must equal to.
So, all we have to do is add them.
JK = KL = LM
7 + 7 + 7 = 21
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The answer is 720
Sum = (6-2) * 180
Sum= 4 * 180
Sum = 720
For the last one, the correct answer is 99
This is too complicated to explain :)
I hope this helps!