1. The problem is to find the slope $m$ of the line passing through the points $(-7,7)$ and $(7,-7)$. 2. The formula for slope between two points $(x_1,y_1)$ and $(x_2,y_2)$ is: $$m = \frac{y_2 - y_1}{x_2 - x_1}$$ 3. Substitute the given points into the formula: $$m = \frac{-7 - 7}{7 - (-7)}$$ 4. Simplify the numerator and denominator: $$m = \frac{-14}{7 + 7}$$ 5. Simplify the denominator: $$m = \frac{-14}{14}$$ 6. Cancel common factors: $$m = \frac{\cancel{-14}}{\cancel{14}} = -1$$ 7. Therefore, the slope of the line is $-1$.