Question

The hypotenuse of a right-angled isosceles triangle is sqrt(72) cm. Find the length of its base.

• A. 6 cm
• B. 7 cm
• C. 8 cm
• D. 9 cm

Answer 1

The correct option is A 6 cm

Hypotenuse = $\sqrt{72}$ cm
By pythagorean theorem,
(Altitude)${}^2$+(Base)${}^2$ = (Hypotenuse)${}^2$
In an isoceles right angled triangle, Altitude = Base
∴ 2(Base)${}^2$ = ${\sqrt{72}}^2$
⇒ 2(Base)${}^2$ = 72
(Base)${}^2$ = 36
Base = $\sqrt{36}$ = 6 cm