Question.
Find the coordinates of the points which divide the line segment joining A (– 2, 2) and B (2,8) into four equal parts.
Find the coordinates of the points which divide the line segment joining A (– 2, 2) and B (2,8) into four equal parts.
Solution:
Here, the given points are A(–2, 2) and B(2, 8)
Let $P_{1}, P_{2}$ and $P_{3}$ divide $A B$ in four equal parts.
$\because \quad \mathrm{AP}_{1}=\mathrm{P}_{1} \mathrm{P}_{2}=\mathrm{P}_{2} \mathrm{P}_{3}=\mathrm{P}_{3} \mathrm{~B}$
Obviously, $\mathrm{P}_{2}$ is the mid-point of $\mathrm{AB}$
$\therefore \quad$ Coordinates of $\mathrm{P}_{2}$ are
$\left(\frac{-\boldsymbol{2}+\boldsymbol{2}}{\boldsymbol{2}}, \frac{\boldsymbol{2}+\boldsymbol{8}}{\boldsymbol{2}}\right)$ or $(0,5)$
Again, $\mathrm{P}_{1}$ is the mid-point of $\mathrm{AP}_{2}$.
$\therefore \quad$ Coordinates of $P_{1}$ are
$\left(\frac{-2+0}{2}, \frac{2+5}{2}\right)$ or $\left(-1, \frac{7}{2}\right)$
Also $\mathrm{P}_{3}$ is the mid-point of $\mathrm{P}_{2} \mathrm{~B}$.
$\therefore \quad$ Coordinates of $\mathrm{P}_{3}$ are
$\left(\frac{0+2}{2}, \frac{5+8}{2}\right) \operatorname{or}\left(1, \frac{13}{2}\right)$
Thus, the coordinates of $P_{1}, P_{2}$ and $P_{3}$ are $\left(-\mathbf{1}, \frac{\mathbf{7}}{\mathbf{2}}\right),(0,5)$ and $\left(\mathbf{1}, \frac{\mathbf{3}}{\mathbf{2}}\right)$ respectively.
Here, the given points are A(–2, 2) and B(2, 8)
Let $P_{1}, P_{2}$ and $P_{3}$ divide $A B$ in four equal parts.
$\because \quad \mathrm{AP}_{1}=\mathrm{P}_{1} \mathrm{P}_{2}=\mathrm{P}_{2} \mathrm{P}_{3}=\mathrm{P}_{3} \mathrm{~B}$
Obviously, $\mathrm{P}_{2}$ is the mid-point of $\mathrm{AB}$
$\therefore \quad$ Coordinates of $\mathrm{P}_{2}$ are
$\left(\frac{-\boldsymbol{2}+\boldsymbol{2}}{\boldsymbol{2}}, \frac{\boldsymbol{2}+\boldsymbol{8}}{\boldsymbol{2}}\right)$ or $(0,5)$
Again, $\mathrm{P}_{1}$ is the mid-point of $\mathrm{AP}_{2}$.
$\therefore \quad$ Coordinates of $P_{1}$ are
$\left(\frac{-2+0}{2}, \frac{2+5}{2}\right)$ or $\left(-1, \frac{7}{2}\right)$
Also $\mathrm{P}_{3}$ is the mid-point of $\mathrm{P}_{2} \mathrm{~B}$.
$\therefore \quad$ Coordinates of $\mathrm{P}_{3}$ are
$\left(\frac{0+2}{2}, \frac{5+8}{2}\right) \operatorname{or}\left(1, \frac{13}{2}\right)$
Thus, the coordinates of $P_{1}, P_{2}$ and $P_{3}$ are $\left(-\mathbf{1}, \frac{\mathbf{7}}{\mathbf{2}}\right),(0,5)$ and $\left(\mathbf{1}, \frac{\mathbf{3}}{\mathbf{2}}\right)$ respectively.