Question

If the distance between the points (8, x) and (4, 4) is 5 units, then x can be

• A.
  5
• B.
  4
• C.
  7
• D.
  8

Answer 1

The correct option is C

7
The distance between two points $(x_1,y_1)and(x_2,y_2)$ is given by $\sqrt{(x_2-x_1{)}^2+(y_2-y_1{)}^2}$

Now, the distance between points $(8,x)$ and (4, 4) is 5 units.

$\therefore \sqrt{(4-8{)}^2+(4-x{)}^2}=5\Rightarrow 16+(x-4{)}^2=25\Rightarrow (x-4{)}^2=25-16=9\Rightarrow x-4=\pm 3\Rightarrow x=7or1$

Hence, the correct answer is option (c).