Help does anyone know this?

(2x - 4)(2x + 7) = 4x^2 +14x - 8x -28

= 4x^2 + 6x -28

(x)(x+3) = x^2 + 3x

(4x^2 + 6x - 28) - ( x^2 + 3x ) = 3x^2 + 3x -28

where does the z at is it on the x axes or on the y axes any way if it is on the y axes put it horizontally and if it is on the x axes put it vertically

except if the answer is in the value of money, then, it will matter. it will have to be $0.40, but i can tell this is not a money question, so .4 should be the right one.