Question 850601
Hello, 
Let's first find the length of the other leg by using Pythagorean Formula:
9^2 + x^2 = (2x)^2
81 = 3x^2
Divide by 3 and sq root:
x = 5.2 (rounded off)
Now that we know the length of the leg we use the triangle formula:
1/2 (5.2)(9)= 23.4 sq units.
Make sense?
RJ
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