Three Dimensional Geometry Question 24

Question 24 - 2024 (31 Jan Shift 2)

A line passes through $A(4,-6,-2)$ and $B(16,-2,4)$. The point $P(a, b, c)$ where $a, b, c$ are non-negative integers, on the line $A B$ lies at a distance of 21 units, from the point $A$. The distance between the points $P(a, b, c)$ and $Q(4,-12,3)$ is equal to

Show Answer

Answer (22)

Solution

$\frac{x-4}{12}=\frac{x+6}{4}=\frac{z+2}{6}$

$\frac{x-4}{\frac{6}{7}\frac{2}{7}}=\frac{y+6}{\frac{3}{7}}=21$

$\left(21 \times \frac{6}{7}+4, \frac{2}{7} \times 21-6, \frac{3}{7} \times 21-2\right)$

$=(22,0,7)=(a, b, c)$

$\therefore \sqrt{324+144+16}=22$