Réponse:
-5x2 +3 = 28
-5x2=28-3
-5x2=25
X2=-25/5
X= - racine de 5
-5x2 +3=-22
-5x2 =-22-3
-5x2=-25
X2=-25/-5
X2=5
X = racine de 5
-5x2+3=-28
-5x2=-28-3
-5x2=-31
X2=-31/-5
X= racine de 31/5
