Question Number 169924 by amin96 last updated on 12/May/22
Commented by som(math1967) last updated on 12/May/22
$${Area}\:{of}\:\bigtriangleup{ABC}\:? \\ $$
Commented by mr W last updated on 12/May/22
$$\frac{\mathrm{8}+\mathrm{6}+\mathrm{12}}{\mathrm{2}}=\mathrm{13} \\ $$$$\Delta_{{DEF}} =\sqrt{\mathrm{13}×\left(\mathrm{13}−\mathrm{8}\right)×\left(\mathrm{13}−\mathrm{6}\right)×\left(\mathrm{13}−\mathrm{12}\right)}=\sqrt{\mathrm{455}} \\ $$$$\Delta_{{ABC}} =\left(\frac{\mathrm{20}}{\mathrm{8}}\right)^{\mathrm{2}} \sqrt{\mathrm{455}}=\frac{\mathrm{25}\sqrt{\mathrm{455}}}{\mathrm{4}} \\ $$
Commented by mr W last updated on 15/May/22
$${see}\:{also}\:{Q}\:\mathrm{170010} \\ $$