How do you do 4x - 9 = 6x - 13? what do you subtract from both sides?

To start, you need to subtract 4x from both sides, that way, x is one one sid of the equation.

Simple

you have: 4x-9=6x-13

-->>Isolate the variable..(x)

4x-9=6x-13
-4x   -4x

-9=2x-13
+13    +13

4=2x

2=x

Plug it in..to make sure it is correct

4(2)-9=6(2)-13

8-9=12-13

-1=-1

Correct.

Thus, your answer.

Aand b are correctly balanced reactions. they have the same number of atoms in both sides of the reaction

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