Question

Calculati aria unui triunghi isoscel care are laturile de 17 cm si baza de 30cm urgentttt dau coroana

Answer 1

Răspuns:

Aria=baza×inaltimea/2

baza=3cm

inaltimea(h) - ?

h la puterea 2 = 17 la puterea a 2 - 15 la puterea a 2

h la puterea a 2 = 289-225 = 64 = 8

h ( inaltimea ) = 8

Aria = 30×8/2 = 120 cm la puterea a 3 (cubi)

Answer 2

Folosim formula lui Heron:

$\it \mathcal{A}=\sqrt{p(p-a)(p-b)(p-c)}\\ \\ \Delta ABC\ -\ isoscel,\ AB=AC=17\ cm,\ \ BC=30\ cm\\ \\ a=30,\ b=c=17,\ p=\dfrac{a+b+c}{2}=\dfrac{30+17+17}{2}=\dfrac{64}{2}=32\\ \\ p-a=32-30=2\\ \\ p-b=p-c=32-17=15\\ \\ \mathcal{A}=\sqrt{32\cdot2\cdot15\cdot15} =\sqrt{64\cdot15^2}=8\cdot15=120\ cm^2$