How do you solve $x^{2} = 21 x$ $x^2=21x$ ?

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Answer 1 · 2015-05-20T15:54:22

$x^{2} = 21 x$ $x^2=21x$

rewriting the equation:
$x^{2} - 21 x = 0$ $x^2 - 21x = 0$

taking out the common term $x$ $x$
$x (x - 21) = 0$ $x( x - 21) = 0$

equating with $0$ $0$
$x = 0 or x - 21 = 0$ $x = 0 or x-21 =0$

$x = 0, 21$ $color(green)(x = 0 ,21$ are the two solutions

Answer 2 · 2015-05-20T15:54:59

$x^{2} = 21 x$ $x^2 = 21x$

$x^{2} - 21 x = 0$ $x^2 - 21x = 0$

$x \cdot (x - 21) = 0$ $x*(x-21) = 0$

$\Rightarrow x_{1} = 0, x_{2} = 21$ $=> x_1 = 0, x_2=21$ .

How do you solve x2=21xx^2=21x?