Question

What is the value of c, if the point $(c,c)$ is at a distance of $\sqrt{18}$ units from the origin?

• A. c = +3
• B. c = -3
• C. c = ±3

Answer 1

The correct option is C c = ±3

Given that $(c,c)$ is $\sqrt{18}$ units from the origin, we can say that:
$\sqrt{{(c-0)}^2+{(c-0)}^2}=\sqrt{18}$
squaring both sides, $2c^2=18c^2=9c=\pm 3$