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Matchstick Equations - Back to the Matchstick Puzzles

Try to rectify a mistake by moving a single matchstick, to get the correct equation.

(Edit: you can not place any matchstick diagonally over the equals sign)

The following equation is made of 11 matches:

XI - V = IV (more solutions)

The following equation is made of 11 matches:

X + V = IV (more solutions)

The following equation is made of 10 matches:

L + L = L (more solutions)

The following equation is made of 12 matches:

VI = IV - III (more solutions)

The following equation is made of 14 matches:

XIV - V = XX

The following equation is made of 11 matches:

IX - IX = V

The following equation is made of 12 matches:

X = VIII - II

The following equation is made of 7 matches:

VII = I

This old topic is locked since it was answered many times. You can check solution in the Spoiler below.

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Matchstick Equations - solution

XI - V = IV (more solutions) ... X - VI = IV or XI - V = VI or XI - VI = V

X + V = IV (more solutions) ... IX - V = IV or X - VI = IV

L + L = L (more solutions) ... C - L = L or L + I = LI

VI = IV – III (more solutions) ... VI = IX – III or VI = IV + II

XIV - V = XX ... XV + V = XX

IX - IX = V ... IX - IV = V

X = VIII – II ... X - VIII = II

VII = I ... square root of 1

• 1
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• 1 month later... What? Confused!

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• 1 month later... Hah, one thing you could do, is pick up a random match, and place it diagonally over the equals sign. Making the statement read, XI (doesnt equal) X.

Share on other sites 1. move the I from XI over to after the V.

XI - V = IV

becomes:

X - VI = IV (10 - 6 = 4)

2. Move the I from the + to make it a -, and move it to after the V.

X + V = IV

becomes:

X - VI = IV (10 - 6 = 4)

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• 2 weeks later... Haha. square root of 1. Ha ha

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• 3 weeks later... Couldn't L + L = L also be changed with a movement of the plus sign matchstick to be L = L = L

and @ mogul, I thought of that same thing

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• 3 weeks later... i say we light all the matches and watch them burn

Share on other sites L+L=L

L+I=L I

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• 2 weeks later... For the last one, why not

From:

VII = I

To:

II-I = I

?

Share on other sites The last one can not be solved

ll-l=l

that moves to many match sticks.

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• 3 weeks later... From:

VII = I

To:

II-I = I

This moves two matchsticks (or, if you look at available space, up to 4). You are allowed to move only 1.

However, for the first problem, I tried this:

XI - V = IV to IX - V = IV (you simply move the "I" from after the X to before it, changing 11 to 9.)

L + L = L I also solved as L = L = L

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• 4 weeks later... A MESSAGE FOR MANUEL

XI - V = IV answers X-VI=IV

X + V = IV ANSWERS X-VI=IV

L + L = L ANSWERS L+I=L I

VI = IV - III ANSWER VI=IV+II

XIV - V = XX ANSWER XV+V=XX

IX - IX = V ???

X = VIII - II ANSWER X-VIII=II

VII = I ???

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• 2 weeks later... L+L=L

remove upright from + and add to first L to make it C for 100-50=50.

Share on other sites For the last one how about:

VII>I

Share on other sites L + L = L (more solutions) ... C - L = L or L + I = LI

?Why C-L=L

L=L=L

Share on other sites IX - IX = V: move slightly one stick from the X to obtain V

IX - IV = V

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• 3 months later... From:

VII = I

To:

II-I = I

This moves two matchsticks (or, if you look at available space, up to 4). You are allowed to move only 1.

However, for the first problem, I tried this:

XI - V = IV to IX - V = IV (you simply move the "I" from after the X to before it, changing 11 to 9.)

L + L = L I also solved as L = L = L

Actually, it moves one matchstick.

You go from \/|| = | to /|-| = |, and of course the / is really just a | at an angle, so ||-|=|. I don't think the meaning was that you couldn't physically move the matchstick to give yourself enough room, you just couldn't change the formation of the sticks outside of moving the one. Otherwise a lot of them aren't solveable.

Edited by NateET
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• 2 months later... XI - V = IV (more solutions) ... X - VI = IV or XI - V = VI or XI - VI = V

Here, using your first solution, you moved four sticks, not one. First, you removed the "I" from "XI." Then you moved the "- V" one spot to the left (moving three sticks). Then you put the "I" back after the "- V" (thus moving the fourth stick).

This problem is apparent in each solution.

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Here, using your first solution, you moved four sticks, not one. First, you removed the "I" from "XI." Then you moved the "- V" one spot to the left (moving three sticks). Then you put the "I" back after the "- V" (thus moving the fourth stick).

This problem is apparent in each solution.

I have moved just 1 matchstick in each solution ... I will use 1 color for the moved matchstick for each of the 3 possible solutions

puzzle:

XI - V = IV

solution 1: X - VI = IV (from XI - V = IV)

solution 2: XI - V = VI (from XI - V = IV)

solution 3: XI - VI = V (from XI - V = IV)

I advise you post at least 1 puzzle in "new puzzles" section, otherwise your account will be locked

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• 2 months later... hmmm well is there anything that says you cant multiply because if you can then the last one is easy

From= II-I=I

To= I x I = I

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• 1 month later... VII = I

√1 = 1 (square root of 1 = 1)

Or you could get "complex" V-II = I

√-1 = i (square root of -1 = i)

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