Question

a = 5, c = 2 Dau coroana varog

Answer 1

Explicație pas cu pas:

$AE = 5 \sqrt{7} \ dam$

$BM = QC = DE = 4 \ dam$

$AD = AE + DE = 5 \sqrt{7} + 4 \ dam$

$Aria (ABCD) = AD^{2} = (5 \sqrt{7} + 4)^{2} = \\ = 175 + 40 \sqrt{7} + 16 = \bf 191 + 40 \sqrt{7} \ {dam}^{2}$

$MQ = BC - 8 = AD - 8 = 5 \sqrt{7} - 4 \ dam$

$Aria (MNPQ) = MQ^{2} = (5 \sqrt{7} - 4)^{2} = \\ = 175 - 40 \sqrt{7} + 16 = \bf 191 - 40 \sqrt{7} \ {dam}^{2}$

=>

$Aria (hasurata) = Aria(ABCD) + Aria(MNPQ) = \\ = 191 + 40 \sqrt{7} + 191 - 40 \sqrt{7} = \bf 382 \ dam^{2}$