How do you solve $x^2 - 12 = 4x$ ?

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Answer 1 · 2018-06-01T14:50:04

See a solution process below:

First, put the equation in standard form:

$x^2 - 12 - color(red)(4x) = 4x - color(red)(4x)$

$x^2- 4x - 12 = 0$

Next, factor the left side of the equation as:

$(x - 6)(x + 2) = 0$

Now, solve each term on the left for $0$ to solve the problem:

Solution 1:

$x - 6 = 0$

$x - 6 + color(red)(6) = 0 + color(red)(6)$

$x - 0 = 6$

$x = 6$

Solution 2:

$x + 2 = 0$

$x + 2 - color(red)(2) = 0 - color(red)(2)$

$x + 0 = -2$

$x = -2$

The Solution Set Is:

$x = {-2, 6}$

How do you solve x^2 - 12 = 4xx^2 - 12 = 4x?