How do you solve $2x - 4 = -4$ ?

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Answer 1 · 2015-11-13T10:38:00

$x=0$
Look at the method. It will help you solve other problems.

Given: $2x-4=-4$

The objective is to get $x$ on its own.

$color(blue)("Step 1")$
Isolate the x-terms

Add 4 to both sides

$( 2x-4) color(brown)(+4) = (-4) color(brown)(+4)$

The purpose of the brackets is to show what part of the previous equation is going to be changed. They serve no other purpose!

$2x +color(brown) ((-4+4)) = color(brown)((-4+4))$

$2x +0 = 0$

$color(blue)("Step 2")$

Divide both sides by 2

$(2x)/(color(brown)(2)) =0/(color(brown)(2)$

$2/(color(brown)(2))x = 0$

$color(green)("But "2/2" is another way of writing "1$

$1 times x = 0$

$x=0$

How do you solve 2x - 4 = -42x - 4 = -4?