How do you solve $-5x^2=-500$ ?

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Answer 1 · 2016-07-26T14:59:30

$x = 10$

This is a good example of how operations can act on both sides of an equation in order to simplify and find the value of a variable.

I'll work this out showing each step:
$-5x^2 = -500$

$(1/-5)(-5x^2) = -500(1/-5)$

$x^2 = 100$

$sqrt(x^2) = sqrt(100)$

$x = 10$

Answer 2 · 2016-07-26T15:04:13

$x=+-10$

Given: $" "color(brown)(-5x^2=-500)$

To make $-5x^2$ positive multiply both sides by (-1)

$" "color(brown)(5x^2=500)$

Divide both sides by $color(blue)(5)$ turning the 5 in $5x^2$ into 1

$" "color(brown)(5/(color(blue)(5))xx x^2=500/(color(blue)(5)))$

$" "color(brown)(x^2=100)$

Square root both sides

$" "color(brown)(sqrt(x^2)=sqrt(100))$

$" "color(green)(x=+-10)$

How do you solve -5x^2=-500-5x^2=-500?