(A) . The inequality is - 3x < 30 + 2x.

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Subtract 2x from each side.

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- 3x - 2x < 30 + 2x - 2x

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- 5x < 30

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Divide each side by negative 5 and reverse the inequality symbol.

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(- 5x) / (- 5) > (5*6) / (- 5)

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Cancel common terms.

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x > - 6.

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(B) . The inequality is x + 3 ≥ 6(x - 4) +7.

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Apply distributive property : a(b - c) = ab - ac.

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x + 3 ≥ 6x - 24 +7

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x + 3 ≥ 6x - 17

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Subtract 3 from each side.

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x + 3 - 3 ≥ 6x - 17 - 3

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x ≥ 6x - 20

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Subtract 6x from each side.

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x - 6x ≥ 6x - 20 - 6x

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- 5x ≥ - 20

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Divide each side by negative 5 and reverse the inequality symbol.

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(- 5x) / (- 5) ≤ (- 5*4) / (- 5)

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Cancel common terms.

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x ≤ 4.

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The formula for the perimeter of the rectangle P = 2(l + w), where l = length and w = width.

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Let x be the length(l) of the rectangle.

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The width(w) of the rectangle = 4 ft shorter than the length = x - 4.

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The perimeter(P) of the rectangle is greater than 72 ft ⇒ P > 72.

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2(l + w) > 72

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2[ x + (x - 4) ] > 72

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x + (x - 4) > 36

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2x - 4 > 36

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2x > 40

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x > 20.

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The length(l) of the rectangle is greater than 20 ft ⇒ x > 20.

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Subtract 4 from each side of the above inequality.

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x - 4 > 20 - 4

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x > 16.

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The width(w) of the rectangle is greater than 16 ft ⇒ x > 16.

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Length : x > 20 and Width : x > 16.