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Hi, I am doing my geometry homework and am stuck on what methods to use to find the area. I tried drawing a bunch of heights but then the picture became so crammed I had to start over. Hints would be AWESOME!

Find the area of triangle ABC:

Hi, I am doing my geometry homework and am stuck on what methods to use to find the-example-1

1 Answer

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The area of triangle ABC is
\( √(15) \) square units.

To find the area of triangle ABC, we can use the fact that the perpendicular bisectors of the sides of a triangle meet at the circumcenter. The circumcenter is equidistant from the vertices of the triangle.

Given that AH = 4, HD = 1, and BD = DC, we can infer that the circumcenter (O) is also the centroid (since the median and perpendicular bisector coincide in an equilateral triangle). Therefore, AO = BO = CO.

Since HD = 1, AH = 4, and AO = BO, we can apply the Pythagorean theorem to find OD:


\[ OD^2 = AO^2 - HD^2 \]


\[ OD^2 = 4^2 - 1^2 \]


\[ OD^2 = 16 - 1 \]


\[ OD^2 = 15 \]

Since BD = DC and OD is the perpendicular bisector of BC, BD = DC =
\( √(15) \). Now, we can find the area of triangle ABC using the area formula:


\[ \text{Area} = (1)/(2) \cdot BC \cdot OD \]


\[ \text{Area} = (1)/(2) \cdot 2 \cdot √(15) \]


\[ \text{Area} = √(15) \]

Therefore, the area of triangle ABC is
\( √(15) \) square units.

User Mohyt
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