How to Put Plus Minus on Calculator

Adding the plus-minus symbol (±) to your calculator can be useful for mathematical expressions, equations, and scientific calculations. This guide explains how to properly input and use this symbol across different calculator types.

What is Plus Minus (±)

The plus-minus symbol (±) indicates that a value can be either positive or negative. It's commonly used in:

Mathematical expressions to show possible outcomes
Scientific measurements with possible error margins
Engineering calculations with tolerances
Statistical ranges

For example, in the expression 5 ± 2, the value could be 3, 5, or 7.

How to Input Plus Minus on Calculator

On Scientific Calculators

Locate the "±" button (often near the "±" or "±" key)
Press the button to toggle between positive and negative values
For expressions like 5 ± 2, enter "5" then press "±" to show "-5"

On Graphing Calculators

Use the "±" key in the equation editor
For statistical functions, use the "±" symbol in data entry

On Computer Keyboards

Use the Alt code: Alt+0177 on Windows or Option+± on Mac
Or type "±" directly if your keyboard supports it

On Mobile Calculators

Look for the "±" button in the symbol pad
For touch keyboards, use the special character menu

Note: Not all calculators support the ± symbol directly. For basic calculators, you may need to enter the values separately and indicate the range in your notes.

Common Uses of Plus Minus

In Mathematical Equations

The ± symbol is often used in equations to represent multiple possible solutions:

x² - 5x + 6 = 0 has solutions x = 2 ± √(4-6)

In Scientific Measurements

When reporting measurements with possible errors:

Length = 10.5 ± 0.2 cm

In Engineering Tolerances

For manufacturing specifications:

Diameter = 50.0 ± 0.5 mm

Examples

Example 1: Simple Expression

Calculate 8 ± 3:

8 + 3 = 11
8 - 3 = 5

Example 2: Measurement Range

A lab reports a temperature as 25.0 ± 0.5°C. This means:

Minimum temperature: 24.5°C
Maximum temperature: 25.5°C

Example 3: Engineering Tolerance

A bolt specification is 12.0 ± 0.1 mm. This means:

Minimum acceptable length: 11.9 mm
Maximum acceptable length: 12.1 mm

FAQ

Can I use ± with decimal numbers?

Yes, the ± symbol works with both whole numbers and decimal numbers. For example, 3.14 ± 0.01 means the value could be 3.13 or 3.15.

Is ± the same as +-?

Yes, ± and +- represent the same concept. The ± symbol is preferred in formal mathematical contexts.

Can I use ± in basic calculators?

Basic calculators typically don't support the ± symbol directly. You'll need to enter the values separately and indicate the range in your notes.