Answer:
x = 12 or
Step-by-step explanation:
Find the length of x for one side of the triangle first. To do this, use the Pythagorean Theorem which states: a² + b² = c² or in this case c² - a² = b². c² is 45 and a² is 3*3 or 9. Subtract 45-9 to get 36. Find the square root of 36 to get 6. The opposite side is also going to have a missing side length of 6 so add 6+6 to get 12 as x.
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