You are being asked to compare various expressions to the given one, and to determine which are equivalent and which are not. You are asked to simplify the given expression—collect terms.
The given expression ...
... 4y -8x² -5 +14x² +y -1
can be simplified by identifying like terms and adding their coefficients.
... y(4 +1) +x²(-8 +14) +(-5 -1)
... = 5y +6x² -6 . . . . . simplified form
Any expression that has a different y-term, a different x² term, or a different constant term is <em>not equivalent</em>.
Once you have found this simplified expression, you can drag it to the appropriate box. Looking at the top three expressions on the left, you see immediately that they have different y-terms, so all those go to the "not equivalent" box. The expression on the bottom row has a different x² term, so it, too, is "not equivalent". (The sign is negative instead of positive. Details matter.)
The remaining expression, the one on the far right, has the appropriate y-term and constant term. The x² terms have not been combined, so it is equivalent, but not fully simplified.
