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

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Answer 1 · 2015-05-20T15:54:22

$x^2=21x$

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

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

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

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

Answer 2 · 2015-05-20T15:54:59

$x^2 = 21x$

$x^2 - 21x = 0$

$x*(x-21) = 0$

$=> x_1 = 0, x_2=21$ .

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