How do you find number 57? Please answer ASAP!!!

The length of the other leg of the right triangle will be 9 units.
The Pythagoras theorem states that the sum of two squares equals the squared of the longest side.
The Pythagoras theorem formula is given as
H² = P² + B²
The triangle ABC is right angle triangle.
The length of hypotenuse is 15, then the one leg is 12,
Then the length of the other leg of the right triangle will be
c² = a² + b²
15² = 12² + b²
225 = 144 + b²
b² = 225 - 144
b² = 81
b = 9
Thus, the length of the other leg of the right triangle will be 9 units.
More about the Pythagoras theorem link is given below.
https://brainly.com/question/343682
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