In a right-angled triangle, the leg and hypotenuse are 40 and 50, respectively. Find the other leg of this triangle.

The proportions of the triangle are the same as those of the famous Egyptian triangle – 3: 4: 5 (leg: leg: hypotenuse). Therefore, you can immediately give the answer: 30 cm.

Just in case, let’s check the Pythagorean theorem:

Let the unknown leg be x. Then the sum of the squares of the leg is equal to the square of the hypotenuse:

x ^ 2 + 402 = 502;

x = √ (2500 – 1600) = √ (900) = 30.

Answer: 30.