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Simplify 3m(2m-1) + 6m(4m-1) Find its value if m = -1/3

User Brasileric
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1 Answer

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Explanation:

3m(2m - 1) + 6m(4m - 1) = 6m² - 3m + 24m² - 6m =

= 30m² - 9m = 3m(10m - 3)

for m = -⅓ we get

30×(-⅓)² - 9×(-⅓) = 30×1/9 - -9/3 = 10/3 + 9/3 =

= 19/3 = 6 = 6.3333333...

as a controls

3×(-⅓)×(10×(-⅓) - 3) = -1×(-10/3 - 3) = 10/3 + 3 =

= 10/3 + 3×3/3 = 10/3 + 9/3 =

= 19/3

correct.

3×(-⅓)×(2×(-⅓) - 1) + 6×(-⅓)×(4×(-⅓) - 1) =

= -1×(-⅔ - 1) + -2×(-4/3 - 1) =

= ⅔ + 1 + 8/3 + 2 = ⅔ + 3/3 + 8/3 + 6/3 = 19/3

correct.

User Sveatoslav
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8.5k points

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