To find the slope of the line that passes through the points \((0, 0)\) and \((2, -2)\), we can use the slope formula:
\[ \text{slope} = \frac{y_2 - y_1}{x_2 - x_1} \]
For the points \((0, 0)\) (where \( x_1 = 0 \) and \( y_1 = 0 \)) and \((2, -2)\) (where \( x_2 = 2 \) and \( y_2 = -2 \)), we substitute into the formula:
\[ \text{slope} = \frac{-2 - 0}{2 - 0} = \frac{-2}{2} = -1 \]
So, the slope of the line is \(-1\).