Question 155402
(a) you are correct M lies in between P and O

MO = 8   PO = 12 and MP = 4

12 = 8 + 4
we can write PO = PM + MO    which shows that M is in between P and O

(b)  
H lies in between EFG and F is the common vertex

so we get  EFH + HFG = EFG
         x + y + 2x - 6 = 90
         3x + y - 6 = 90
             y = 90 - 3x + 6
             y = 96 - 3x


I hope this is clear to you.
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