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In △ABC, AD¯¯¯¯¯, BD¯¯¯¯¯, and CD¯¯¯¯¯ are angle bisectors of the vertex angles. If BE = 12 meters and BD = 20 meters, what is DG? Enter your answer in the box.

User ManojN
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Final answer:

To find DG in triangle ABC, we can use the angle bisector theorem and the property that the sum of the lengths of the segments of an angle bisector is equal to the length of the side opposite that angle. First, use the angle bisector theorem to find the ratio of AD to CD. Then, use the property that the sum of the lengths of the segments of an angle bisector is equal to the length of the side opposite that angle. Finally, find DG by taking half of CD.

Step-by-step explanation:

In triangle ABC, angle bisectors of the vertex angles are AD, BD, and CD. Given that BE = 12 meters and BD = 20 meters, we need to find DG.

First, we can use the angle bisector theorem to find the ratio of AD to CD. The theorem states that the ratio of the lengths of the segments of the angle bisectors is equal to the ratio of the lengths of the sides opposite those angles. So, we have:

AD/CD = AB/BC

Since AD and CD are angle bisectors and BD is a side, we can substitute the given values:

AD/20m = AB/BC

Next, we can use the property that the sum of the lengths of the segments of an angle bisector is equal to the length of the side opposite that angle. So, we have:

AD + CD = BC

Substituting the values we know, we have:

20m + CD = BC

Combining the two equations, we can solve for AD and CD:

AD/20m = AB/BC --> AD = AB/BC * 20m

20m + AD = BC --> AD = BC - 20m

Solve the two equations for AD and CD, we get:

AD = 40m/(1 + AB/BC)

CD = BC - AD

Now we can find the value of DG. Since AD and CD are angle bisectors, they bisect the angle at D. Therefore, DG is half of CD:

DG = 0.5 * CD

User Frodopwns
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