Answer:
x = √77
or
x = 8.77
Step-by-step explanation:
it's a right triangle
Pythagorean theorem
the sum of the squares on the legs of a right triangle is equal to the square on the hypotenuse
x² = 9² - 2²
x² = 81 - 4
x² = 77
x = √77
or
x = 8.77
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