SOLUTION: What is the area in the figure below, in m^2? https://imgur.com/a/mBEHVsO

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Question 1199847: What is the area in the figure below, in m^2?
https://imgur.com/a/mBEHVsO

Found 2 solutions by ikleyn, MathTherapy:
Answer by ikleyn(52777) About Me  (Show Source):
You can put this solution on YOUR website!
.

The large triangle has the leg 7 meters and the hypotenuse 25 meters.


Hence, its other leg is  sqrt%2825%5E2-7%5E2%29 = 24 meters.


The area of the large triangle is  %281%2F2%29%2A7%2A24 = 7*12 = 84 m^2.


The small triangle is similar to the large triangle with the similarity coefficient 4:7, or  4%2F7
(from the smaller to the larger).


Hence, the area of the smaller triangle is  %284%2F7%29%5E2%2A84 = %2816%2A12%29%2F7 = 192%2F7 = 27 3%2F7 = 27.43  m^2  (rounded).    ANSWER

Solved.



Answer by MathTherapy(10551) About Me  (Show Source):
You can put this solution on YOUR website!
What is the area in the figure below, in m^2?
https://imgur.com/a/mBEHVsO

You can use the fact that if the sides of similar triangles are in a certain ratio, then their areas'
ratio  will be the SQUARED VALUES of that ratio. 
Area of larger ΔABC = 1%2F2(AB)(AC) = 1%2F2(7)(24) = 7(12) = 84 m2.
So, shorter leg (ED) of smaller ΔCED to shorter leg of larger ΔABC results in a  4%2F7 ratio. 
Thus, the area of smaller ΔCED will be: 
OR

Larger ΔABC and smaller ΔCED (shaded) are SIMILAR.
Larger ΔABC boasts a 7-24-25 Pythagorean Triple, and AB and AC on larger ΔABC are 7 and 24 m, respectively.
Using triangular similarity (larger ΔABC to smaller ΔCED) theory to find segment EC on smaller ΔCED, we get: matrix%282%2C3%2C+AB%2FAC%2C+%22=%22%2C+ED%2FEC%2C+7%2F24%2C+%22=%22%2C+4%2FEC%29
7EC = 4(24) ---- Cross-multiplying 
matrix%281%2C6%2C+EC%2C+%22=%22%2C+4%2824%29%2F7%2C+%22=%22%2C+96%2F7%2C+m%29. With lengths of EC and ED (longer and shorter legs of ΔCED) being 96%2F7 and 4,
                      we get:  
                                                                matrix%281%2C4%2C+%22=%22%2C+1%2F2%2C+%22%2A%22%2C+%2896%2F7%294%29
                                                                matrix%282%2C2%2C+%22=%22%2C+%2896%2F7%292%2C+%0D%0A%22=%22%2C+192%2F7%29