Answer:
21 = -10m - 3
Add 3 to both sides:
24 = -10m
Divide by -10 on both sides:
-2.4 = m
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Given information
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Area = 40ft²
Length = √20 ft
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Formula
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Area = Length x Width
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Find Width
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40 = √20 x width
Width = 40 ÷ √20
Width = 40 ÷ 2√5
Width = 20 ÷ √5

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