(x^2+4)^2 + 32 = 12x^2 + 48 .... a = x^2 + 4
<span>(x^2 + 4)^2 + 32 = 12(x^2 + 4) </span>
<span>a^2 + 32 = 12a </span>
<span>a^2 - 12a + 32 = 0 </span>
<span>(a - 8)(a - 4) = 0 </span>
<span>a = 8 and a = 4 </span>
<span>for a = 8 ... 8 = x^2 + 4 ... x^2 = 4 ... x = +/- 2 </span>
<span>for a = 4 ... 4 = x^2 + 4 ... x^2 = 0 ... x = 0 </span>
<span>x = -2, 0, +2 so your answer is going to be e
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You have to give more explanation
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Surface area of the cube
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6(2.5 x 2.5) = 37.5m²
<em>(* Each area is 2.5 x 2.5, and there are 6 sides to the cube)</em>
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Surface area of the rectangle prism
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2(11 x 7) + 2(9 x 7) + 2(9 x 11) = 478m²
<em>(* The opposite side of the rectangle area is the same, therefore x2)
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Overlapping area
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2.5 x 2.5 = 6.25m²
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Surface area of the composite figure
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37.5 + 478 - 2(6.25) = 503m²
<em>(* The bottom of the cube and the top of the rectangle prism overlapped, so the area is overlapped twice, minus 2 times of that area)</em>
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Answer: 503m²
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2.25 as a fraction is 2 1/4
