The hypotenuse of a right-angled triangle is 51, leg 45. Find another leg.

Given:
The hypotenuse of a right triangle is 51.
The length of one leg is 45.

The square of the hypotenuse is equal to the sum of the squares of the legs.
Let the unknown leg be x.
Let’s make the equation:
51 ^ 2 = 45 ^ 2 + x ^ 2;
2601 = 2025 + x ^ 2;
x ^ 2 = 2601 – 2025;
x ^ 2 = 576;
x = √576;
x = 24.
Answer: the second leg is 24.