Question

OFER COROANA!!!!!!!!!​

Answer 1

Răspuns:

Prb.1

Ştim ca un triunghi e echilateral daca are toate laturile congruente si toate unghiurile congruente.

a) Cum AB=BC=AC= 5 cm => ΔABC echilateral

b) AB= 4 cm

AC= 0,4 dm=0,4*10 cm=4 cm

BC= 40 mm= 40:10= 4 cm

Deci AB=AC=BC= 4 cm =>  ΔABC echilateral

c) AB=AC= 6 cm.

P ΔABC= 18 cm => AB+BC+AC=18 <=> 2AB+BC=18 <=> 2*6+BC=18 => BC=6 cm.

DEci AB=AC=BC=6 cm =>  ΔABC echilateral

d)∡A≡∡B≡∡C =>  ΔABC echilateral

e) ∡A=∡B= 60°

∡A+∡B+∡C=180° => 2*∡A + ∡C= 180 => 2*60+∡C=180 => ∡C=60°.

Deci ∡A=∡B=∡C=60° =>  ΔABC echilateral

Prb 2

P Δ= 3*l=3*8= 24 cm

Prb 3

PΔ = 33 cm

PΔ= 3*l         ==> 3*l=33 => l=11 cm

Sper că te-am ajutat!