xy=aa²+a-2=0a1+a2=-1 U a1*a2=-2a1=-2 U a2=11)xy=-22x+y=3⇒y=3-2x3x-2x²+2=02x²-3x-2=0D=9+16=25x1=(3-5)/4=-0,5⇒y1=3+1=4x2=(3+5)/4=2⇒y2=3-4=-12)xy=12x+y=3⇒y=3-2x3x-2x²-1=02x²-3x+1=0D=9-8=1x3=(3-1)/4=0,5⇒y3=3-1=2x4=(3+1)/4=1⇒y4=3-2=1(-0,5;4);(2;-1);(0,5;2);(1;1)