How do you solve #-x-3=1#?

2 Answers
Jan 26, 2016

#x=-4,-x=4#

Explanation:

#-x-3=1#

#rarr-x-3=1#

#rarr-x=1+3=4#

#So,-x=4,x=-4#

Feb 3, 2016

A very slightly different way of saying the same thing!

#x=-4#

Explanation:

Given: #-x-3=1#
'~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
#color(blue)("Objective")#

#color(brown)("To end up with ( +x ) on one side of the equals sign and everything")##color(brown)("else on the other side.")#

'~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
#color(blue)("Multiply everything by (-1)")#

#+x+3=-1#

#color(blue)("Subtract 3 from both sides")#

#x +3-3 = -1-3#

#x+0=-4#

#x=-4#

'~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
#color(purple)("Shortcut method")#

Given: #-x-3=1#

Using the rule that for + or - swapping sides of the equals sign changes the sign of the value.

#x=-3-1 #

#x=-4#