Question

What is the length of the diagonal of a square whose area is 162 cm²?

• A. 15 cm
• B. 19 cm
• C. 18 cm
• D. 14 cm

Answer 1

Answer:

C. 18 cm

Solution

$a^2 = 162$

$a = \sqrt{162} = \sqrt{81 \times 2} = 9\sqrt{2}$

Diagonal of a square:$d = a\sqrt{2}$

Substitute value:$d = 9\sqrt{2} \times \sqrt{2}$

$d = 9 \times 2 = 18$