Question

An irrational number is marked on the number line (D) as shown in the figure below. Then the value of CD is ______.

Answer 1

By Pythagoras theorem we know that,

$A{C}^2=A{B}^2+C{B}^2$

$A{C}^2=(3{)}^2+(1{)}^2$

$A{C}^2=9+1$

⇒ $AC=\surd 10$

∴ The value of $CD$ is $\surd 10$.