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NCSM is a parallelogram with diagonals NS and MC that intersect at point P. If NP=4a+20, NS=13a, PC=a+b and PM=2b-2, find CM. Please show work.

User AJFarkas
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Final answer:

To find the length of diagonal CM in parallelogram NCSM, we use the properties of a parallelogram's diagonals bisecting each other and set up equations based on the given lengths to solve for a and b.

Step-by-step explanation:

The question asks us to find the length of diagonal CM in parallelogram NCSM. Since the diagonals NS and MC intersect at point P, they bisect each other in a parallelogram. First, we express the lengths given in terms of a and b:

  • NP = 4a + 20
  • NS = 13a
  • PC = a + b
  • PM = 2b - 2

Knowing that NP + PS = NS and PM + PC = MC, we can write:

  • 4a + 20 + PS = 13a (since NP + PS = NS)
  • 2b - 2 + a + b = MC (since PM + PC = MC)

To find PS, we rearrange the first equation:

PS = 13a - (4a + 20) = 9a - 20

Since PS = PC (diagonals bisect each other), we now have:

9a - 20 = a + b

This allows us to find the relationship between a and b. After solving these equations, we use the second relationship (PM + PC = MC) to find CM.

User Kuba Birecki
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