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I need help with this

I need help with this-example-1
User Shevek
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1 Answer

9 votes

Answer:

30 square cm

Explanation:

Key skills needed are: Triangle similarity, multiplication, proportions, subtraction

1) We first find that Triangle BCD is similar to triangle ACE. This is because they both have 1 right angle, and both share Angle BCD. Therefore, the other two angles are also the same measure.

2) Based on the statement above, 6/9 = 8/CE (CE just means the length of CE)

3) Solve this by cross multiplying -


(6)/(9) = (8)/(ce)

This means that 6(CE) = 8(9)

4) Multiply it out: 6(CE) = 72

5) Divide by 6 and get CE = 12 cm.

6) Then use base time height to find the area of both triangles.

7) For triangle BCD: 6(8)/2 = 6(4) = 24 square centimeters

8) For Triangle ACE: 9(12)/2 = 9(6) = 54 square cm

9) To find the area of ABDE, you would subtract the are of triangle ACE by the area of triangle BCD

10) This is 54 - 24 = 30 square cm.

Hope you understood and have a nice day!! :D

User Mike Bobbitt
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4.9k points