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In trapezoid ABCD AC is a diagonal and ∠ABC ≅ ∠ACD. Find AC if the lengths of the bases BC and AD are 14m and 28m respectively.

2 Answers

2 votes

Final answer:

To find the length of AC, the diagonal in trapezoid ABCD, we can use the fact that ∠ABC ≅ ∠ACD and the lengths of the bases BC and AD. By setting up a proportion using the corresponding sides of the similar triangles ABC and ACD, we can find that AB/AC = 1/2. Multiplying the length of AB by 2 gives us AC = 28m.

Step-by-step explanation:

Given that ∠ABC ≅ ∠ACD and the lengths of the bases BC and AD are 14m and 28m respectively, we can find the length of AC, which is a diagonal in trapezoid ABCD.

  1. Because the two angles are congruent, triangle ABC is similar to triangle ACD. This means their corresponding sides are proportional.
  2. We can set up a proportion using the corresponding sides of the triangles:

    BC/AD = AB/AC
  3. Substituting the values, we get 14/28 = AB/AC. Simplifying this equation gives us AB/AC = 1/2.
  4. Since the lengths of AB and AC have a ratio of 1/2, we can determine AC by multiplying the length of AB by 2.
  5. Therefore, AC = 2 * AB = 2 * 14 = 28m.
User Znkr
by
8.0k points
2 votes

Answer:


AC=14√(2)m

Step-by-step explanation:

we are given trapezoid ABCD

AC is a diagonal

∠ABC ≅ ∠ACD

we know that

BC and AD are parallel

so, <DAC = <ACB

so, ΔABC ≅ΔACD

Since, both triangles are similar

so, their ratios must be equal

we get


(BC)/(AC) =(AC)/(AD)

now, we can plug values


(14)/(AC) =(AC)/(28)


AC^2=14* 28


AC^2=14^2* 2


AC=14√(2)m


User Greg Oks
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8.1k points