What Is Negative 1 Minus Negative 2? | Minus A Negative, Add

Subtracting −2 from −1 gives 1, since taking away a negative adds its positive.

Negative numbers can feel slippery until you pin down what the minus sign is doing. In this one problem, you’re dealing with two different jobs for “minus”: one minus is an operation (subtract), and the other minus is a sign (a negative value). Once you separate those roles, the answer becomes steady and repeatable.

Let’s work it out, then lock in the rule so you can handle any “minus a negative” problem without guessing.

Start With The Expression And Solve It

You’re asked to compute:

−1 − (−2)

Read it like this: start at −1, then subtract −2. Subtracting a negative means you’re removing a debt, removing a loss, or removing a move to the left. Removing a negative pushes you in the positive direction.

So you rewrite the subtraction as addition:

−1 − (−2) = −1 + 2

Now it’s straightforward:

−1 + 2 = 1

That’s the whole result: 1.

What Is Negative 1 Minus Negative 2? Worked Out

If you want the clean “do-this-every-time” move, use this one sentence:

Subtracting a negative turns into adding a positive.

Apply it here:

• Keep the first number the same: −1
• Change “minus” to “plus”
• Flip the sign of the second number: −2 becomes +2

That gives: −1 + 2 = 1.

Negative 1 Minus Negative 2 With Sign Rules That Never Break

People mix this up because they try to do two things at once: handle subtraction and handle negative signs. A cleaner approach is to convert subtraction into addition, then add integers like you already know how.

Use The “Add The Opposite” Rule

Any subtraction problem can be rewritten using “add the opposite”:

a − b = a + (−b)

This is not a trick. It’s a definition that keeps integer arithmetic consistent across number lines, equations, and algebra.

Now plug your values into the rule:

a = −1 and b = −2

So:

−1 − (−2) = −1 + (−(−2))

The opposite of −2 is +2, so you get:

−1 + 2 = 1

Why “Minus A Negative” Becomes Plus

Think of subtraction as “take away.” If the thing you take away is negative, you’re taking away something that points left on the number line. Taking away a leftward move is the same as moving right.

That’s why teachers often say “minus a negative becomes plus.” It’s a shortcut phrase for the more precise statement: replace subtraction with addition of the opposite.

See It On A Number Line In One Clean Move

A number line view is great because it turns symbols into motion.

Step 1: Start At −1

Put your finger (or your mental marker) on −1.

Step 2: Subtract −2 Means “Take Away Negative 2”

Subtracting −2 means you remove a move of 2 units to the left. Removing that left move leaves you with a move of 2 units to the right.

Step 3: Move Right 2 Spaces

From −1, move right two steps: to 0, then to 1.

You land at 1.

If you want a guided explanation with visuals and practice problems, OpenStax walks through integer subtraction models in their Prealgebra text. The section titled “Subtract Integers” uses concrete models that match this same rule set.

Three Ways To Check Your Answer Fast

Checking builds confidence. Here are three quick checks that don’t rely on luck.

Check 1: Convert To Addition And Recompute

−1 − (−2) becomes −1 + 2. Add: 1. Same result.

Check 2: Reverse The Operation

If −1 − (−2) = 1, then starting from the result and adding the subtracted amount should return the starting number.

Take 1 and add −2:

1 + (−2) = −1

You’re back where you started, so the subtraction is consistent.

Check 3: Use A “Difference” View

Subtraction asks for a difference: what number added to (−2) gives (−1)?

Find x such that:

(−2) + x = −1

x must be 1. That matches the computed answer.

Common Confusions And How To Avoid Them

Most mistakes come from letting the symbols blur together. Here’s what to watch for.

Mixing Up The Operation Minus And The Negative Sign

In “−1 − (−2),” the middle minus is an operation. The minus in (−2) is part of the number. Treat them as different things.

Dropping Parentheses Too Early

Parentheses matter because they keep the second number intact. Keep them until you rewrite subtraction as addition of the opposite:

−1 − (−2) = −1 + 2

Flipping The Wrong Sign

Only the second number changes sign when you convert subtraction to addition. The first number stays the same.

Table Of Integer Subtraction Patterns You Can Reuse

When you face a new problem, match it to a pattern. Then rewrite it in a single step.

Subtraction Form	Rewrite As Addition	What Usually Happens
a − b (both positive)	a + (−b)	Moves left by b
a − (−b) (subtract a negative)	a + b	Acts like addition
(−a) − b	(−a) + (−b)	Sum gets more negative
(−a) − (−b)	(−a) + b	Can cross zero
0 − (−b)	0 + b	Becomes positive b
0 − b	0 + (−b)	Becomes negative b
a − a	a + (−a)	Always 0
(−a) − (−a)	(−a) + a	Always 0

Why This Rule Matters In Algebra, Not Just Arithmetic

This one subtraction shows up all over algebra. The moment you start solving equations, you’ll subtract negative numbers during “move this term to the other side” steps.

Say you have:

x − (−2) = −1

Replacing subtraction with addition keeps your steps clean:

x + 2 = −1

Then subtract 2 from both sides:

x = −3

The same habit makes your work easier when you simplify expressions like:

−4 − (−7) + 3

Rewrite first:

−4 + 7 + 3

Then add in a steady order. No guesswork. No symbol wrestling.

A Mental Picture That Stays Simple

If number lines aren’t your thing, try a “change” view: subtraction tells you how much you change when you go from the second number to the first.

From −2 to −1, you move one step to the right. That move is +1. So the difference between −1 and −2 is 1, matching the result.

This is also why the answer feels positive: −1 is greater than −2. When the starting point is greater than what you subtract, your result tends to be positive.

Practice With The Same Move, No Extra Tricks

Try these in your head. Use the same rewrite each time: change subtraction into addition of the opposite.

• 3 − (−5) = 3 + 5
• −6 − (−4) = −6 + 4
• 0 − (−9) = 0 + 9
• −2 − 7 = −2 + (−7)

If you want short practice sets with instant feedback, Khan Academy’s page on “Subtracting negative numbers review” uses the same rewrite and reinforces it with repetition.

Table Of Mistakes That Flip The Answer

When your result feels off, it’s usually one of these slips.

Slip	What To Do Instead
Changing the first number’s sign	Keep the first number the same; only flip the second number
Dropping parentheses and losing the negative	Keep parentheses until you rewrite as addition of the opposite
Thinking “minus minus” always means “minus”	Replace subtraction with addition, then flip the second number
Adding absolute values without thinking about direction	Use a number line or compare magnitudes and keep the correct sign
Rushing across zero	Count steps: from −1, two steps right lands on 1
Trying to memorize too many special cases	Use one rule: a − b = a + (−b)

One Sentence You Can Carry Into Any Problem

If you want a single move that works every time, stick with this:

Rewrite subtraction as addition of the opposite, then add.

Using that move, −1 − (−2) becomes −1 + 2, which equals 1. Once you’ve done it a few times, the result starts to feel natural, not mysterious.