Practicing Success
The point of intersection of the lines $\frac{x+1}{3}=\frac{y+3}{5}=\frac{z+5}{7}$ and $\frac{x-2}{1}=\frac{y-4}{3}=\frac{z-6}{5}$ is : |
$\left(\frac{1}{3},-\frac{1}{3},-\frac{2}{3}\right)$ $\left(\frac{1}{2},-\frac{1}{2},-\frac{3}{2}\right)$ $\left(\frac{1}{2}, \frac{1}{2}, \frac{1}{2}\right)$ $\left(\frac{1}{3}, \frac{1}{3}, \frac{1}{3}\right)$ |
$\left(\frac{1}{2},-\frac{1}{2},-\frac{3}{2}\right)$ |
Any point on the first line is (3r1 – 1, 5r1 – 3, 7r1 – 5) and any point on the second line is (r2 + 2, 3r2 + 4, 5r2 + 6) At the point of intersection, we must have 3r1 – 1 = r2 + 2, 5r1 – 3 = 3r2 + 4 7r1 – 5 = 5r1 + 6 Thus, $r_1=\frac{1}{2}, r_2=-\frac{3}{2}$ Hence required point is $\frac{3}{2}-1, \frac{5}{2}-3, \frac{7}{2}-5$ i.e. $\left(\frac{1}{2},-\frac{1}{2},-\frac{3}{2}\right)$ |