Question

Find k, if R(1, –1), S (–2, k) and slope of line RS is –2.

Answer 1

Slope of line RS is –2
Slope of RS will be
$$\begin{gathered} \frac{y_2-y_1}{x_2-x_1}=\frac{k-\left(-1\right)}{-2-1}=\frac{k+1}{-3}=-2 \\ \Rightarrow k+1=6 \\ \Rightarrow k=5 \end{gathered}$$