Mathematics - Properties of Triangle Question with Solution | TestHub

MathematicsProperties of TriangleGeneral (basic formula based)Medium2 minQB
MathematicsMediumsingle choice

Positive x,y,z satisfy ++=25, +=9, and +xz+=16. Find xy+2yz+.

Options:

Answer:
B
Solution:

Construct a triangle of sides 3,4,5 with an interior point P whose distances to vertices are x,y,z and whose central angles between corresponding radial segments are 150°,90°,120°. The three given equations are the cosine rules for the three small triangles. Their areas sum to 6: 6=(1/2)xy sin150°+(1/2)yz sin90°+(1/2)xz sin120° =xy/4+yz/2+/4. Multiply by 4 to get 24. Numerical positive solution also verifies ≈24.

Stream:JEESubject:MathematicsTopic:Properties of TriangleSubtopic:General (basic formula based)
⏱ 2mℹ️ Source: QB

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