1) 10rad14-8rad49-18rad4+15rad14
= 10rad14-56-36+15rad14
=25rad14-92
2) 3x-1*4x*5 = 3x-4x*5 = 3x-20x = -17x
II
1) facem pitagora : x- latura ; 64 = x^2 + x^2
64 = 2x^2
=>x^2 = 32
=>x = rad 32 = 4rad2 e latura
P = 4rad2 * 4 = 16rad2 cm
A = (4rad2)^2 = 32 cm patr.
2) P: 4*10 = 40 cm
A: l *l * sin dintre laturi = 10*10* sin 60 = 100*rad3/2 = 100rad3/2 = 50rad3 cm patr.
3) EB = 12-9 = 3 cm
tr. CEB pitagora : 25= 9 + CE^2
CE^2= 16
CE = 4cm =DA
=> P : 9+5+12+4 =30 cm
A : (12+9)*4/2 = 42 cm patr.
Sper ca te-am ajutat !
PS : nu cred ca exista baza oblica