How do you solve #x+3=2x-5#?

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Answer 1 · 2015-11-13T18:47:55

x = 8

x+3=2x−5

You want to isolate the "x" on one side, so subtract "x" from one side and move it over to the other side with "2x."

3 = 2x - x - 5

Then move the -5 to the other side by changing the sign (-5 to +5) and adding it to the other side.

3 + 5 = 2x - x

Solve it and you should result with 8 = x.

Answer 2 · 2015-11-13T19:55:43

More detail given

Given that: #x+3=2x-5#

Grouping like terms with #x# on the right to keep it positive and everything else on the other side.

Add #color(blue)(5)# to both sides.

#(x+3) color(blue)(+5) = (2x -5) color(blue)(+5)#
The brackets only function is to show what is being changed

#x +(3+5) = 2x + (-5 +5)#

#x+8 =2x +0#

Subtract #color(blue)(x)# from both sides

#(x+8) -color(blue)(x) = (2x) -color(blue)(x)#

but #2x -> 2 " of "x " so " 2x = x+x#

#8 + (x color(blue)(-x)) = x + (x-color(blue)(x))#

# 8 +0=x +0#
#8=x#

Convention is that #x# is on the left so reverse

#x=8#
.