Find the slope of line BC.

a) Determine the equation of line BC.

Step 1: Find the slope of line BC.
The coordinates of B are $(1,-2)$ and C are $(-5,4)$.
The slope $m$ is given by the formula $m = \frac{y_2 - y_1}{x_2 - x_1}$.

$$m_{BC} = \frac{4 - (-2)}{-5 - 1} = \frac{4 + 2}{-6} = \frac{6}{-6} = -1$$

Step 2: Use the point-slope form to find the equation of line BC.
Using point B$(1,-2)$ and slope $m_{BC} = -1$:

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