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Given: △ABC, D∈ AB , E∈ BC F∈ AC , DE ∥ AC , AD ∥ FE AD=6, DE=5, AB=17 Find: AC

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Given: △ABC, D∈ AB , E∈ BC F∈ AC , DE ∥ AC , AD ∥ FE AD=6, DE=5, AB=17 Find: AC Please-example-1
User Vfedorkov
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1 Answer

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Answer: The length of AC is approximately 5.196 units.

Explanation:

To find the length of AC, we can use the fact that DE is parallel to AC and AD is parallel to FE, which forms a pair of corresponding angles. Therefore, we can set up a proportion using the fact that corresponding angles are congruent.

DE/AC = AD/FE

We know that DE = 5 and AD = 6, so we can substitute these values into the proportion:

5/AC = 6/FE

We can cross-multiply and solve for AC:

5 * FE = 6 * AC

Next, using the fact that triangle ABC is a triangle, we can use the Pythagorean theorem to find the value of FE.

AB^2 + BC^2 = AC^2

17^2 + BC^2 = (AC)^2

289 + BC^2 = AC^2

Now, substitute the value of FE into the equation we have,

5 * sqrt(AC^2 - 289) = 6 * AC

multiply the both sides of the equation by the reciprocal of 5,

sqrt(AC^2 - 289) = (6/5) * AC

Square both sides of the equation,

AC^2 - 289 = 36/25 * AC^2

subtract the left side from the right side

-289 = -(36/25) * AC^2

divide both sides by -(36/25)

AC = sqrt(289/(1-(36/25)))

AC = sqrt(289/11/25)

AC = sqrt(289/275)

AC = sqrt(289/11)

AC = sqrt(26)

AC = approx 5.196152422706632

Therefore, the length of AC is approximately 5.196 units.

User Wonda
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