In the figure:http://i57.tinypic.com/29ggy1u.jpg,D and E are the points lying on AC and AB respetively such that BE:AE =AD:DC=2:1.BD andCE intersects at K .Find EK:KC
In the figure:http://i57.tinypic.com/29ggy1u.jpg,D and E are the points lying on AC and AB respetively such that BE:AE =AD:DC=2:1.BD andCE intersects at K .
Find EK:KC ?
We set the angles:angle ABD =B angle ADB =D angle BKE = angle BKC =KWe set the line segments:line segment BE =b line segment AE =a line segment CD =c line segment DA =d line segment EK =p line segment KC =q
I.
sin(B)d=sin(D)a+b⇒sin(B)sin(D)=da+b
II.
sin(180−D)=sinDsin(D)q=sin(K)c⇒q=c⋅sin(D)sin(K)
III.
sin(K)b=sin(B)p⇒p=b⋅sin(B)sin(K)
IV.
\dfrac{p}{q} = \dfrac{ b \cdot \dfrac {\sin{(B)}} {\sin{(K)}} } { c \cdot \dfrac{\sin{(D)}}{\sin{(K)}} } } =\dfrac {b} {c} \cdot \dfrac{\sin{(B)}}{\sin{(D)}} } =\dfrac {b} {c} \cdot \left(\dfrac{d}{a+b} \right) \\\\ = \dfrac {1} { \dfrac{c}{d} }\cdot \left(\dfrac {1}{ \dfrac{a+b}{b} } \right) = \dfrac {1} { \dfrac{c}{d} }\cdot \left(\dfrac {1}{ \dfrac{a}{b}+\dfrac{b}{b} } \right) = \dfrac {1} { \dfrac{c}{d} }\cdot \left(\dfrac {1}{ \dfrac{a}{b}+1 } \right)\\\\\\ \dfrac{c}{d} = \dfrac{a}{b} = \dfrac{1}{2} \\\\ \dfrac{p}{q} =2\cdot \left(\dfrac {1}{ \dfrac{1}{2}+1 } \right) = 2\cdot \left(\dfrac {1}{ \dfrac{3}{2} }\right) =2\cdot \dfrac{2}{3} \\\\ \boxed{\dfrac{p}{q} = \dfrac{4}{3}}
EK:KC = 4 : 3
In the figure:http://i57.tinypic.com/29ggy1u.jpg,D and E are the points lying on AC and AB respetively such that BE:AE =AD:DC=2:1.BD andCE intersects at K .
Find EK:KC ?
We set the angles:angle ABD =B angle ADB =D angle BKE = angle BKC =KWe set the line segments:line segment BE =b line segment AE =a line segment CD =c line segment DA =d line segment EK =p line segment KC =q
I.
sin(B)d=sin(D)a+b⇒sin(B)sin(D)=da+b
II.
sin(180−D)=sinDsin(D)q=sin(K)c⇒q=c⋅sin(D)sin(K)
III.
sin(K)b=sin(B)p⇒p=b⋅sin(B)sin(K)
IV.
\dfrac{p}{q} = \dfrac{ b \cdot \dfrac {\sin{(B)}} {\sin{(K)}} } { c \cdot \dfrac{\sin{(D)}}{\sin{(K)}} } } =\dfrac {b} {c} \cdot \dfrac{\sin{(B)}}{\sin{(D)}} } =\dfrac {b} {c} \cdot \left(\dfrac{d}{a+b} \right) \\\\ = \dfrac {1} { \dfrac{c}{d} }\cdot \left(\dfrac {1}{ \dfrac{a+b}{b} } \right) = \dfrac {1} { \dfrac{c}{d} }\cdot \left(\dfrac {1}{ \dfrac{a}{b}+\dfrac{b}{b} } \right) = \dfrac {1} { \dfrac{c}{d} }\cdot \left(\dfrac {1}{ \dfrac{a}{b}+1 } \right)\\\\\\ \dfrac{c}{d} = \dfrac{a}{b} = \dfrac{1}{2} \\\\ \dfrac{p}{q} =2\cdot \left(\dfrac {1}{ \dfrac{1}{2}+1 } \right) = 2\cdot \left(\dfrac {1}{ \dfrac{3}{2} }\right) =2\cdot \dfrac{2}{3} \\\\ \boxed{\dfrac{p}{q} = \dfrac{4}{3}}
EK:KC = 4 : 3
I haven't had time to digest this one, heureka.....but it looks pretty impressive!!
That really does look VERY impressive Heureka.
Hopefully I will have time to examine it properly later, because I don't have it now.
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Hi anon, Please read this post.
How to upload an Image.
http://web2.0calc.com/questions/how-to-upload-an-image-nbsp_1
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I have put the question and answer together for other peopl's benefit :))
In the figure:http://i57.tinypic.com/29ggy1u.jpg,D and E are the points lying on AC and AB respetively such that BE:AE =AD:DC=2:1.BD andCE intersects at K .Find EK:KC
Here is the pic