Answer
-$\frac{1}{4}$
Work Step by Step
$x^{2}$ - 3xy - 2$y^{2}$ =
We substitute x=$\frac{1}{2}$ and y=$\frac{1}{4}$ into the expression and simplify:
$(\frac{1}{2})^{2}$ - 3 $\times$ $\frac{1}{2}$ $\times$ $\frac{1}{4}$ - 2 $\times$ $(\frac{1}{4})^{2}$ =
$\frac{1}{4}$ - $\frac{3}{8}$ - $\frac{2}{16}$ =
We need to change the denominator of each fraction to 16.
$\frac{1}{4}$ $\times$ $\frac{4}{4}$ - $\frac{3}{8}$ $\times$ $\frac{2}{2}$- $\frac{2}{16}$ =
$\frac{4}{16}$ - $\frac{6}{16}$ - $\frac{2}{16}$ =
- $\frac{4}{16}$ =
-$\frac{1}{4}$
