## The Mathematical Symbol "Minus-or-Plus Sign (∓)"

The ∓ Symbol in Mathematics: The Minus-Or-Plus Sign

Mathematical notation is rich with symbols that convey precise meanings, and among them is the ∓ symbol, representing the "Minus-Or-Plus Sign". This article offers insights into the usage and significance of the ∓ symbol, supplemented by illustrative examples.

## Usage

The primary function of the ∓ symbol is to denote that either subtraction or addition can be used in a given context. Often seen alongside its counterpart, the "plus-minus sign" (±), the ∓ sign indicates the reverse order, meaning "minus or plus".

## Examples

• Example 1: When expressing solutions to certain quadratic equations, the ∓ can be used. If a quadratic has solutions expressed as:
$$x = a ± b$$
The counterpart solution can be written as:
$$x = a ∓ b$$
• Example 2: In some contexts, the ∓ sign can be used for clarity when the sequence of operations matters. For instance, when subtracting before adding:
$$y = c ∓ d$$
Here, one might first subtract d from c and then consider adding d to c.

In summary, while the ∓ symbol is less common than its counterpart ±, it holds a specific meaning in mathematical contexts. Recognizing and understanding this notation aids in grasping nuanced mathematical expressions and operations.

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## Codes for the ∓ Symbol

 The Symbol ∓ Alt Code Alt 8723 HTML Code ∓ HTML Entity ∓ CSS Code \2213 Hex Code ∓ Unicode U+2213

## How To Insert the ∓ Symbol

(Method 1) Copy and paste the symbol.

The easiest way to get the ∓ symbol is to copy and paste it into your document.

Bear in mind that this is a UTF-8 encoded character. It must be encoded as UTF-8 at all stages (copying, replacing, editing, pasting), otherwise it will render as random characters or the dreaded �.

(Method 2) Use the "Alt Code."

If you have a keyboard with a numeric pad, you can use this method. Simply hold down the Alt key and type 8723. When you lift the Alt key, the symbol appears. ("Num Lock" must be on.)

(Method 3) Use the HTML Decimal Code (for webpages).

HTML TextOutput
<b>My symbol: &#8723;</b>My symbol: ∓

(Method 4) Use the HTML Entity Code (for webpages).

HTML TextOutput
<b>My symbol: &mnplus;</b>My symbol: ∓

(Method 5) Use the CSS Code (for webpages).

CSS and HTML TextOutput
<style>
span:after {
content: "\2213";}
</style>
<span>My symbol:</span>
My symbol: ∓

(Method 6) Use the HTML Hex Code (for webpages and HTML canvas).

HTML TextOutput
<b>My symbol: &#x2213;</b>My symbol: ∓
On the assumption that you already have your canvas and the context set up, use the Hex code in the format 0x2213 to place the ∓ symbol on your canvas. For example:
JavaScript Text
const x = "0x"+"E9"
ctx.fillText(String.fromCodePoint(x), 5, 5);
Output

(Method 7) Use the Unicode (for various, e.g. Microsoft Office, JavaScript, Perl).

The Unicode for ∓ is U+2213. The important part is the hexadecimal number after the U+, which is used in various formats. For example, in Microsoft Office applications (e.g. Word, PowerPoint), do the following:
TypeOutput
2213
[Hold down Alt]
[Press x]

(The 2213 turns into ∓. Note that you can omit any leading zeros.)
In JavaScript, the syntax is \uXXXX. So, our example would be \u2213. (Note that the format is 4 hexadecimal characters.)
JavaScript TextOutput
let str = "\u2213"
document.write("My symbol: " + str)
My symbol: ∓