Question

The base of an isosceles right triangle is $30cm$. Find its area.

• A. $225$ $c{m}^2$
• B. $225\sqrt{3}c{m}^2$
• C. $5\sqrt{2}c{m}^2$
• D. $6\sqrt{3}c{m}^2$

Answer 1

Answer: (A)

$225$ $c{m}^2$

In right angle isosceles $△ABC$,

${2a}^2=900\Rightarrow a^2=450$

$\Rightarrow a=\sqrt{450}=15\sqrt{2}cm$

Therefore, ar $△ABC=\frac{1}{2}\times a\times a=\frac{1}{2}\times 15\sqrt{2}\times 15\sqrt{2}=225{cm}^2$