Selection B is appropriate.
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It takes 12 times as long to fill the whole tank as it does to fill 1/12 of the tank.
.. 12 * (1/3 hour) = (1/3)*12 hour
The angle that is next to 9x should be 180 - 9x because it is a straight angle.
Since there are 180 degrees in an angle we can add up the values to 180 and solve for x.
180- 9x + 5x + 9 + x = 180
-3x = -9
x = 3
Hope this helped!
Answer: 81 mm^2
Step-by-step explanation: All the sides are the same length and area is just length * width so 9*9=81. You're welcome
