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)#