19 lines
422 B
Markdown
19 lines
422 B
Markdown
---
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tags:
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- prealgebra
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---
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## Addition, subtraction
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Addition is the inverse of subtraction: $$(x - a) + a = x$$ $$ (6 - 2) + 2 = 6
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$$
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Subtraction is the inverse of addition: $$(x + a) - a = x$$ $$ (3 + 2) - 2 = 3$$
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Division is the inverse of multiplication $$ \frac{a \cdot x}{a} = x$$
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$$ \frac{6
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\cdot 3}{6} = 3$$
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Multiplication is the inverse of division $$ a \cdot \frac{x}{a} = x$$
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$$ 2 \cdot
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\frac{8}{2} = 8$$
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