How do you multiply $(5 m - 1) (6 m - 5)$ $(5m-1)(6m-5)$ ?

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Answer 1 · 2018-05-31T00:44:40

$30 m^{2} - 31 m + 5$ $30m^2-31m+5$

$(5 m - 1) (6 m - 5)$ $(5m-1)(6m-5)$

= $5 m (6 m - 5) - 1 (6 m - 5)$ $5m(6m-5)-1(6m-5)$

= $30 m^{2} - 25 m - 6 m + 5$ $30m^2-25m-6m+5$

= $30 m^{2} - 31 m + 5$ $30m^2-31m+5$

Answer 2 · 2018-05-31T01:06:04

$30 m^{2} - 31 m + 5$ $30m^2 - 31m + 5$

$(5 m - 1) (6 m - 5)$ $(5m-1)(6m-5)$

To multiply/simplify this, we use FOIL:
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First, multiply out the $firsts$ $color(teal)("firsts")$ :
$5 m \cdot 6 m = 30 m^{2}$ $color(teal)(5m * 6m = 30m^2)$

Then the $outers$ $color(indigo)("outers")$ :
$5 m \cdot - 5 = - 25 m$ $color(indigo)(5m * -5 = -25m)$

Now the $inners$ $color(darkorange)("inners")$ :
$- 1 \cdot 6 m = - 6 m$ $color(darkorange)(-1 * 6m = -6m)$

Finally the $lasts$ $color(forestgreen)"lasts"$ :
$- 1 \cdot - 5 = 5$ $color(forestgreen)(-1 * -5 = 5)$

Now combine them all together:
$color(teal)(30m^2) quadcolor(indigo)(-quad25m) quadcolor(darkorange)(-quad6m) quadcolor(forestgreen)(+quad5)$

We can still combine the like terms $-25m - 6m$ :
$30m^2 - 31m + 5$

Hope this helps!

How do you multiply (5m-1)(6m-5)(5m−1)(6m−5)(5m-1)(6m-5)?