Respuesta :

popinapot
Y=(1/2)x^2 + 2x - 1
3x - y = 1, or y=3x-1
substitute
3x-1=(1/2)x^2+2x-1
0=(1/2)x^2-x
0=x(0.5x-1)
x=0,2
y=2+4-1=5
3(2)-1=5.
When x=2 y=5 (2,5) is one solution
when x=0, y=-1, (0,-1) is the other solution