In the question, it is given that area of triangle ABC is 2 times the area of triangle ABD ‌‌
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x(y+z)=2(‌
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xy) ‌y+z=2y ‌y=z Triangles ABC and ABD are right-angled triangles. ‌W2=x2+4y2 ‌W2=x2+y2+3y2 ‌AD2=x2+y2 ‌AD2=W2−3y2 ‌AD=√W2−3y2 The answer is option C.