The base of a right-angled triangle is 10 units and its hypotenuse is 20 units. What is its area (in square units, approximately)?
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → 86.6
The third side (the height on the base) comes from Pythagoras’ theorem; then area \(\displaystyle =\frac{1}{2}\times\text{base}\times\text{height}\).
Height \(=\sqrt{20^2-10^2}=\sqrt{300}=10\sqrt{3}\approx17.32\)
Area \(\displaystyle =\frac{1}{2}\times10\times10\sqrt{3}=50\sqrt{3}\approx86.6\) square units
