How do you solve $(2 m + 3) (4 m + 3) = 0$ $(2m + 3)(4m + 3) = 0$ ?

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How do you solve $(2 m + 3) (4 m + 3) = 0$ $(2m + 3)(4m + 3) = 0$ ?

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Answer 1 · 2018-03-14T11:39:52

$m = - 12, - 6$ $m=-12, -6$

Explanation:

Multiply the equation using FOIL

$(2 m + 3) (4 m + 3) = 0$ $( 2m + 3 ) ( 4m + 3 ) = 0$
$(2 m \cdot 4 m) + (2 m \cdot 3) + (3 \cdot 4 m) + (3 \cdot 3) = 0$ $(2m * 4m) + (2m * 3) + (3 * 4m) + (3 * 3) = 0$
$8 m^{2} + 6 m + 12 m + 9 = 0$ $8m^2 + 6m + 12m + 9 = 0$
$8 m^{2} + 18 m + 9 = 0$ $8m^2 + 18m + 9 = 0$

Since it would be sort of difficult to factor mentally,
we use the quadratic equation
(or just keep plugging in factors till you get the answer)

$\frac{- b \pm \sqrt{b^{2} - 4 a c}}{2 a}$ $(- b +- sqrt(b^2 - 4ac))/(2a)$

$\frac{- (18) \pm \sqrt{{(18)}^{2} - 4 (8) (9)}}{2 (8)}$ $(-(18) +- sqrt((18)^2 - 4(8)(9)))/(2(8))$

$\frac{- 18 \pm \sqrt{324 - 288}}{16}$ $(-18 +- sqrt(324-288))/16$

$\frac{- 18 \pm \sqrt{36}}{16}$ $(-18 +- sqrt(36))/16$

$\frac{- 18 \pm 6}{16}$ $(-18+-6)/16$

$\frac{- 9 \pm 3}{8} = 0$ $(-9+-3)/8=0$

$m = - 12, - 6$ $m=-12, -6$

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How do you solve $(2 m + 3) (4 m + 3) = 0$ $(2m + 3)(4m + 3) = 0$ ?

1 Answer

Explanation:

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Science

Math

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How do you solve (2m+3)(4m+3)=0(2m + 3)(4m + 3) = 0?

1 Answer

Explanation:

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How do you solve $(2 m + 3) (4 m + 3) = 0$ $(2m + 3)(4m + 3) = 0$ ?