$\"\"$

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The slope m of a non vertical line through any two points is given by, \ \

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$\"\"$

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Substitute $\"\"$ in rate of change

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formula.

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$\"\"$

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$\"\"$ \

$\"\"$ (Subtract: 8 – 4 = 4)

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$\"\"$ (Multiply each side by x–2)

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$\"\"$ (Cancel common terms)

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$\"\"$

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$\"\"$ (Distributive property: a(b + c) = ab + ac)

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$\"\"$ (Multiply: $\"\"$ )

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$\"\"$ (Add 4 to each side) \ \

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$\"\"$ (Additive inverse property: $\"\"$ )

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$\"\"$ (Divide each side by -2) \ \

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$\"\"$ (Cancel common terms)

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$\"\"$ (Divide: $\"\"$ )

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$\"\"$

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The value of $\"\"$ .

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