Question

If the distance between the points (4, p) and (1, 0) is 5, then p = ___

• A. $\pm 4$
• B. $\pm 2$
• C. $\pm 2\sqrt{2}$
• D. $\pm 4\sqrt{2}$

Answer 1

The correct option is A

$\pm 4$

Distance between the points (d) = 5
Using distance formula, we get
$\Rightarrow \sqrt{(x_2-x_1{)}^2+(y_2-y_1{)}^2}=d$
$\Rightarrow \sqrt{(4-1{)}^2+(p-0{)}^2}=5\Rightarrow 9+p^2=25\Rightarrow p^2=16\therefore p=\pm 4$