Question

2x + 3y =2 ; x- y upon 2 = 1 upon 2 (cramer's rule)

Answer 1

I dont think that drawing a curve is good approach here.... because we have a square function involved... let me know if you like below approach... otherwise i can draw on xy plane also...

Statement 1 : obviously suff... it tells 2x-3y = -2 
we know x^2 will always be positive is if 2x-3y = -2 (a negative number) .... 2x-3y will always be less than x^2 

given inequlity 2x-3y-x^2<0
2x-x^2-3y<0
(2x-x^2) - 3y < 0 

Statement 2 :
for x > 2 , 2x-x^2 will always be negative 
for y > 0. -3y will always be negative 
so the whole expression will always be negative... Suff