Complete the equation of the line through $(-8,8)$ and $(1,-10)$. Use exact numbers.

Step 1 ：Given two points (-8,8) and (1,-10), we need to find the equation of the line passing through these points.

Step 2 ：The equation of a line in slope-intercept form is given by $y=mx+b$, where $m$ is the slope of the line and $b$ is the y-intercept.

Step 3 ：The slope of the line passing through two points $(x_1,y_1)$ and $(x_2,y_2)$ is given by $m=\frac{y_2-y_1}{x_2-x_1}$.

Step 4 ：Substituting the given points into the slope formula, we find that $m=-2.0$.

Step 5 ：Once we have the slope, we can substitute one of the points and the slope into the equation to solve for $b$. Doing this, we find that $b=-8.0$.

Step 6 ：Substituting $m$ and $b$ into the equation of the line, we get the final equation of the line: $y=-2x-8$.

Step 7 ：$\boxed{{\displaystyle y=-2x-8}}$ is the final answer.