MHB Calculate the area of a triangle knowing its 3 heights

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The discussion focuses on calculating the area of a triangle using its three heights, specifically ha = 3 m, hb = 4 m, and hc = 5 m. Participants are prompted to consider the use of Heron's formula and the semi-sum of the reciprocals of the altitudes to derive the area. The area is estimated to be around 10.03 m² to 10.05 m², with a note that using an online calculator like TrianCal can assist in visualizing the results. The conversation emphasizes the mathematical relationships between the triangle's heights and its area. Accurate calculations are essential for determining the correct area based on the given heights.
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Calculate the area of a triangle knowing its 3 heights

ha = 3 m
hb = 4 m
hc = 5 m

NOTE = You can use the online triangle calculator TrianCal to see and draw the results.
NOTE = Do not use the values ??of responses.

A) 10.03 m2
B) 10.04 m2
C) 10.05 m2
D) Imposible
 
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greg1313 said:
Can you apply Heron's formula?
thanks...
Next, denoting the altitudes from sides a, b, and c respectively as ha, hb, and hc, and denoting the semi-sum of the reciprocals of the altitudes as H = (h_a^{-1} + h_b^{-1} + h_c^{-1})/2 we have[11]

A^{-1} = 4 \sqrt{H(H-h_a^{-1})(H-h_b^{-1})(H-h_c^{-1})}.
 
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