How do you solve $6 x^{2} - 30 x = 36$ $6x ^ { 2} - 30x = 36$ ?

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Answer 1 · 2017-03-13T19:21:33

6 and -1

$6 x^{2} - 30 x - 36 = 0$ $6x^2-30x-36=0$

$D = 30^{2} - 4 \cdot (- 36) \cdot 6 = 1764 = 42^{2}$ $D=30^2-4*(-36)*6=1764=42^2$

$x_{1} = \frac{30 + 42}{12} = 6$ $x_1=(30+42)/(12)=6$

$x_{2} = \frac{30 - 42}{12} = - 1$ $x_2=(30-42)/12=-1$

Answer 2 · 2017-03-13T20:04:37

$x = 6 or x = - 1$ $x = 6 " or " x =-1$

$6 x^{2} - 30 x - 36 = 0 \leftarrow \div 6$ $6x^2 -30x -36 =0" "larr div 6$

$(x^{2} - 5 x - 6) = 0 \leftarrow$ $(x^2 -5x -6) =0" "larr$ find the factors

$(x - 6) (x + 1) = 0$ $(x-6)(x+1)=0$

Either of the factors could be equal to 0.

$x - 6 = 0 \Leftrightarrow x = 6$ $x-6=0" "hArr " "x=6$
$x + 1 = 0 \Leftrightarrow x = - 1$ $x+1 =0" "hArr" "x=-1$

How do you solve 6x2−30x=366x ^ { 2} - 30x = 36?