MHB Ratio of the area of triangles

AI Thread Summary
The area of triangle ABC is twice that of triangle BCD, leading to the conclusion that the area of triangle BEG is one-eighth of triangle ABC and one-half of triangle CFG. The midpoint theorem is applied, confirming that triangle CFG has an area that is one-fourth that of triangle CAB. The relationship between the areas of triangles CFG and CAB is established through their similarity, with a corresponding side ratio of 1/2. The discussion emphasizes the use of geometric properties to derive area ratios effectively. Understanding these relationships is crucial for solving similar geometric problems.
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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)
 
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