Dan je četverokut

takav da

. Ako

, kolika je površina tog četverokuta?
A quadrilateral

is given such that

. If

, what is the area of that quadrilateral?
[lang=hr]
Dan je četverokut $ABCD$ takav da $\angle BAD+\angle BCD=180$. Ako $AB=7, BC=20, CD=24, AD=15$, kolika je površina tog četverokuta?
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[lang=en]
A quadrilateral $ABCD$ is given such that $\angle BAD+\angle BCD=180$. If $AB=7, BC=20, CD=24, AD=15$, what is the area of that quadrilateral?
[/lang]