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Can anybody help me on this

Can anybody help me on this-example-1
User Allenyllee
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1 Answer

2 votes

Answer: second option

Explanation:

Find the distance AE by subtracting AB and DC and dividing by 2:


AE=(AB-DC)/(2)\\\\AE=(15ft-7ft)/(2)\\\\AE=4ft

Knowing the length of AD and AE, you can apply the Pythagorean Theorem to calculate the length DE:


c=√(a^2-b^2)

Where "a" is the hypotenuse and "b" and "c" are the legs of the triangle.

Then:


a=AD=5ft\\b=AE=4ft\\c=DE

Substituting values into
c=√(a^2-b^2) you get that the lenght of DE is:


DE=√((5ft)^2+(4ft)^2)\\DE=3ft

Calculate thea area of the trapezoid with the formula:


A=(h)/(2)(B+b)

Where h is the height, B is the larger base and b is the smaller base.

Substituting, you get:


h=DE=3ft\\B=AB=15ft\\b=DC=7ft\\\\A=(3ft)/(2)(15ft+7ft)=33ft^2

User Murtaza
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