Question

Un trapez isoscel are laturile 24 , 12 ,12 , 12 . Aria lui este ...?

Va rog repede!!

Answer 1

$\it \mathcal{A}=\sqrt{(p-a)(p-b)(p-c)(p-d)}\\ \\ p=\dfrac{24+12+12+12}{2}=30\ cm\\ \\ p-a=30-24=6cm\\ \\ p-b=p-c=p-d=30-12=18cm\\ \\ \mathcal{A}=\sqrt{6\cdot18\cdot18\cdot18}=\sqrt{3\cdot2\cdot18\cdot18^2}=\sqrt{3\cdot36\cdot18^2}=\\ \\ =6\cdot18\sqrt3=108\sqrt3\ cm^2$