SECONDARY GEOMETRY (OWN)
Let a circle $[_{1}$ be drawn through the vertices $A,B$ of $triangle_ ABC$ touching $BC$ at $B$. Similarly drtaw the circle $[_{2}$ passing through $A,C$ touching $BC$ at $C$.Cord $AB$ produces an angle of $45^0$ at the center of $[_{1}$. Cord $AC$ produces an angle of $60^0$ at the center of $[_{2}$.If the radii of $[_{1}$ and $[_{2}$ are 5 & 7 respectively, then find the area of $triangle_ABC$.
GEOMETRY
- Phlembac Adib Hasan
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Re: GEOMETRY
$AB=\sqrt{2.5^2\frac {\sqrt {2}-1} {\sqrt {2} } },AC=\sqrt {2.7^2 \frac {1} {2} }$ [cosine rule]
$ \angle ABC=22.5^0, \angle ACB=30^0 $
So $\angle BAC=127.5^0 $
So $ (\triangle ABC)=\frac {1} {2} \sqrt{2.5^2\frac {\sqrt {2}-1} {\sqrt {2} } } \sqrt {2.7^2 \frac {1} {2} }\; sin\; 127.5^0 $.
$ \angle ABC=22.5^0, \angle ACB=30^0 $
So $\angle BAC=127.5^0 $
So $ (\triangle ABC)=\frac {1} {2} \sqrt{2.5^2\frac {\sqrt {2}-1} {\sqrt {2} } } \sqrt {2.7^2 \frac {1} {2} }\; sin\; 127.5^0 $.
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- nafistiham
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Re: GEOMETRY
try to use the equation editorSANZEED wrote:SECONDARY GEOMETRY (OWN)
Let a circle $[_{1}$ be drawn through the vertices $A,B$ of $triangle_ ABC$ touching $BC$ at $B$. Similarly drtaw the circle $[_{2}$ passing through $A,C$ touching $BC$ at $C$.Cord $AB$ produces an angle of $45^0$ at the center of $[_{1}$. Cord $AC$ produces an angle of $60^0$ at the center of $[_{2}$.If the radii of $[_{1}$ and $[_{2}$ are 5 & 7 respectively, then find the area of $triangle_ABC$.
\[\sum_{k=0}^{n-1}e^{\frac{2 \pi i k}{n}}=0\]
Using $L^AT_EX$ and following the rules of the forum are very easy but really important, too.Please co-operate.
Using $L^AT_EX$ and following the rules of the forum are very easy but really important, too.Please co-operate.