Question

alege raspunsul corect ex 6
dau coroana​

Answer 1

$2AV²=AB² \\ 2AV²=36 \\ AV²=18 \\ AV = 3 \sqrt{2} \: cm \\ \\\small A_{ ΔVAB} = \frac{3 \sqrt{2} \times 3 \sqrt{2} }{2} = \frac{3 \times 2 \times 3}{2} = 9 \: cm {}^{2} \\ \\ \implies \: A _{\ell} = 3 \times 9 = 27 \: cm {}^{2} \\ \\ A_{ ABC} = \frac{\ell {}^{2} \sqrt{3} }{4} = \frac{36 \sqrt{3} }{4} = 9 \sqrt{3} \: cm {}^{2} \\ \\ \\ \iff \: A_{t} = 27 + 9 \sqrt{3} = \boxed{9(3 + \sqrt{3} ) \: cm {}^{2} }$