Three Dimensional Geometry

$\overline{\mathrm{r}}=(-\hat{\mathrm{i}}-\hat{\mathrm{j}}-\hat{\mathrm{k}})+\lambda(\hat{\mathrm{i}}+2 \hat{\mathrm{j}}+\hat{\mathrm{k}})$

$\overline{\mathrm{r}}=(-\hat{\mathrm{i}}-\hat{\mathrm{j}}+\hat{\mathrm{k}})+\lambda(2 \hat{\mathrm{i}}+2 \hat{\mathrm{j}}+\hat{\mathrm{k}})$

$\frac{x+1}{3}=\frac{y+1}{2}=\frac{z+1}{-1}$

$\frac{x-1}{3}=\frac{y-1}{2}=\frac{z+1}{1}$