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In ║ABC║,║AB║=10,║AC║=18.And M is their midpoint, if ║MN║=2. calculate ║BC║

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Final answer:

The length of segment BC in triangle ABC is calculated using the midpoint and the Pythagorean theorem, resulting in an approximate length of 18.36 units.

Step-by-step explanation:

To calculate the length of segment BC in triangle ABC, we need to use the properties of triangles and the given information.

Since M is the midpoint of AC, segment AM is equal to segment MC, which are both half of AC. Given that AC is 18, AM and MC are each 9 units long.

Since M is also the midpoint of BC, and MN is a segment perpendicular to BC with a length of 2 units, triangle MNB is a right-angled triangle (with NB being the hypotenuse and MN being the height).

Using the Pythagorean theorem (a² + b² = c²), we can solve for NB:

  • Let NB = x
  • MN² + NM² (which is AB² because AB = NM) = x²
  • 2² + 9² = x²
  • 4 + 81 = x²
  • 85 = x²
  • x = √85
  • NB = √85 <=> BC = 2 x NB (since M is the midpoint of BC)
  • BC = 2 x √85
  • BC ≈ 18.36 units

Therefore, the length of BC is approximately 18.36 units.

User Supun Kavinda
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