Question

The square root of 0.09 +2 x 0.21 + 0.49 is

• A. $\sqrt{0.09}+\sqrt{0.49}$
• B. $2\sqrt{0.21}$
• C. 1
• D. 0.58

Answer 1

The correct option is C 1

$\sqrt{0.09+2\times 0.21+0.49}$

$\Rightarrow \sqrt{(0.3{)}^2+2\times 0.3\times 0.7+(0.7{)}^2}$

$\because (a+b{)}^2=a^2+2ab+b^2$

$\therefore \sqrt{(0.3+0.7{)}^2}=\sqrt{1}=1$