Solving One Variable Equations by UNWRAPPING

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Suppose we are trying to
SOLVE: 2x + 3 = 13 Dilemma: What should be done first?
Should we divide by 2 or subtract 3?.
(One explanation is to follow "PMDAS in REVERSE!")
Subtract 3 from both sides,
then divide both sides by 2.

Here is another explanation:
Let's pretend that x is like a box.
Suppose we put 5 into the x-box.
Let's think of the expression
"2x + 3"
as a wrapped package.
We need to unwrap the package
to look inside the x-box!

"X" is wrapped first with
paper having
"MULTIPLY by 2"
as the pattern on the paper.

Then on top of the paper we have
a RIBBON with
"ADD 3"
as the pattern on the ribbon.

To unwrap "2x+3" we first
"CUT the RIBBON" ("SUBTRACT 3")

and our second task is to
"TAKE-OFF the paper" ("DIVIDE by 2").

Performing these same tasks on the
right side of the equation will produce:

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