Let R be the point (3, 7) and let P and Q be two points on the line x + y = 5 such that PQR is an equilateral triangle, Then the area of ΔPQR is
\(\frac{25}{4\sqrt3}\)
\(\frac{25\sqrt3}{2}\)
\(\frac{25}{\sqrt3}\)
\(\frac{25}{2\sqrt3}\)
The Correct Option is D
Solution and Explanation
The correct answer is (D) : \(\frac{25}{2\sqrt3}\)
Altitude of equilateral triangle,
\(\frac{\sqrt3l}{2}=\frac{5}{\sqrt2}\)
\(l=\frac{5\sqrt2}{\sqrt3}\)
Area of triangle
\(=\frac{\sqrt3}{4}l^2=\frac{\sqrt3}{4}.\frac{50}{3}=\frac{25}{2\sqrt3}\)
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Concepts Used:
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The central idea in coordinate geometry is to assign numerical coordinates to points in a plane or space, which allows us to describe their positions and relationships using algebraic equations. The most common coordinate system is the Cartesian coordinate system, named after the French mathematician and philosopher René Descartes.