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Answer:
8 units
Step-by-step explanation:
In a 45°- 45°- 90° triangle the legs are congruent, thus
3x - 10 = x + 2 ( subtract x from both sides )
2x - 10 = 2 ( add 10 to both sides )
2x = 12 ( divide both sides by 2 )
x = 6
Thus
3x - 10 = 3(6) - 10 = 18 - 10 = 8
Since legs are congruent then they are both 8 units