Ratio of the area of triangles

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mathlearn
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In the figure , the area of triangle $ABC$ is twice that of triangle $BCD$.USing the given information , find the ration of the area of the triangle $CFG$ to the area of triangle $BEG$

Hint- Use the midpoint theorem.

(Wave) Stuck in this problem & currently I have no workings to show.
 
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mathlearn said:
In the figure , the area of triangle $ABC$ is twice that of triangle $BCD$.USing the given information , find the ration of the area of the triangle $CFG$ to the area of triangle $BEG$

Hint- Use the midpoint theorem.

(Wave) Stuck in this problem & currently I have no workings to show.
Note that $G$ is the mid-point of $BC$. Thus we have
$$[BEG]=(1/2)[BGD]=(1/4)[BCD]=(1/8)[ABC]=(1/2)[CFG]$$
 
caffeinemachine said:
Note that $G$ is the mid-point of $BC$. Thus we have
$$[BEG]=(1/2)[BGD]=(1/4)[BCD]=(1/8)[ABC]=(1/2)[CFG]$$

Many Thanks caffeinemachine (Happy)

Is the area of $\triangle CFG \frac{1}{2}$ the area of $\triangle CAB$?
 
mathlearn said:
Many Thanks caffeinemachine (Happy)

Is the area of $\triangle CFG \frac{1}{2}$ the area of $\triangle CAB$?
No. The area of $CFG$ is 1/4-th the area of $CAB$. This is easy to show. One way to show it is use the fact that $CFG$ and $CAB$ are similar triangles with corresponding side ratio's $1/2$.
 
caffeinemachine said:
No. The area of $CFG$ is 1/4-th the area of $CAB$. This is easy to show. One way to show it is use the fact that $CFG$ and $CAB$ are similar triangles with corresponding side ratio's $1/2$.

Thank you very much again (Sun)