Using the Pythagorean Theorem, it is found that the unknown side length of the triangle is of 7.9 cm.
The Pythagorean Theorem relates the length of the legs [tex]l_1[/tex] and [tex]l_2[/tex] of a right triangle with the length of the hypotenuse h, according to the following equation:
[tex]h^2 = l_1^2 + l_2^2[/tex]
Researching this problem on the internet, we have that:
Hence:
x² + 9² = 12²
x = sqrt(12² - 9²)
x = 7.9 cm.
The unknown side length of the triangle is of 7.9 cm.
More can be learned about the Pythagorean Theorem at https://brainly.com/question/654982
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