# Target Test Prep Sample GRE Quantitative Comparison Problem

2x + 2y = – 4 and $\frac{\mathrm{z}}{2}=\mathrm{x}+\mathrm{y}$

#### Quantity A:

z

#### Quantity B:

z^{2}

We must determine the value of z to solve for both Quantity A and Quantity B. We are given two equations: 2x + 2y = –4 and $\frac{\mathrm{z}}{2}=\mathrm{x}+\mathrm{y}$.

With these two equations we can produce a unique value for z. The first equation can be reduced to

x + y = –2. We can substitute –2 for x + y in equation two to yield $\frac{\mathrm{z}}{2}=-2\to \mathrm{z}=-4$. Since z is negative, z^{2 }is greater than z.

Thus, Quantity B is greater than Quantity A.