a=-5/2
Step-by-step explanation:
-6a=-5-8a
-6a+8a=-5-8a+8a
2a=-5
a=-5/2
Answer:

Step-by-step explanation:
Surface area is the sum of all sides of the area. Since it is a rectangular prism, each surface area will be multiplied by two to account for the opposite side (ex. top and bottom are the same area).
The front/back area is
or 11. So the sum of the areas is 22.
The right/left area is
or 2. So the sum of the areas is 4.
The top/bottom area is
or 22. So the sum of the areas if 44.
We add these together to find the surface area.

The surface area is 
4 + 2x = 12
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Take away 4 from both sides:
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2x = 8
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Divide by 2 on both sides:
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x = 4
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Answer: x = 4
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A quadrilateral is a shape with 4 sides, regardless of their lengths, angles, or symmetry.
Therefore, a square is always a quadrilateral.