Find the area of the quadrilateral in the figure.
A. 13.64
B. 22.25
C. 19.64
D. 15.25
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The answer is option C.
This is a composite figure made up from a right angled triangles ( with sides 3, 4 and 5) and an isoceles triangle with 2 sides both equal to 6.
Area of the right angled triangle = 1/2 * 3 * 4 = 6 sq units.
Height of the isosceles triangle = sqrt (6^2 - 2.5^2) = 5.454
Its area = 1/2 * 5 * 5.454 = 13.635
So area of the whole figure = 19.64 sq units