The answer is 42.80 , 2.28 is what they saved and i got the .80 cents because i rounded up from .78
An object in geometry with no width, length or height is a point
X = # of cans of tomatoes, y = # of cans of corn
x + y = 32.....y = 32 - x
0.80x + 0.40y = 18
0.80x + 0.40(32 - x) = 18
0.80x + 12.8 - 0.40x = 18
0.80x - 0.40x = 18 - 12.8
0.40x = 5.2
x = 5.2 / 0.40
x = 13 <=== 13 cans of tomatoes were bought
leaving (32 - 13) = 19 cans of corn bought

Delta equation is:

but we are interested in

because it determines the discriminant


which means that discriminant is positive :)
Answer:
you'll look back on this and say how easy this is you got it. but for today the bottom one is (3,0) the middle one is (2,3) and the top one is (4,4)