Cero más diez es diez.

The accent in más is required because it is the word for more or plus.

It helps distinguish it from mas without an accent, which is a more formal/literary word meaning but.

So in math:

• más = plus
• mas = but

In this sentence, más means plus, so the accent is necessary.

Here, es is used because the whole expression cero más diez is being treated as one calculation or one result.

So the idea is:

• zero plus ten = one mathematical expression
• that expression is ten

That is why es sounds natural.

Also, in Spanish, math statements are often said this way:

• Dos más dos es cuatro
• Cinco menos uno es cuatro

You may also hear other patterns in arithmetic, especially with y:

• Dos y dos son cuatro

So es in your sentence is completely normal.

Es is the he/she/it is form of the verb ser.

In this sentence, it works like equals or is in English math language.

So:

• Cero más diez es diez = Zero plus ten is ten = Zero plus ten equals ten

Spanish often uses ser in basic equations.

A simple Latin American pronunciation guide:

• cero → SEH-ro
• más → mahs
• diez → roughly dyes

Whole sentence:

• Cero más diez es diez
• roughly: SEH-ro mahs dyes es dyes

A few helpful notes:

• In most of Latin America, z is pronounced like s, so diez sounds like dies/dyes, not like the Spain pronunciation with th.
• The stress is:
  • CE-ro
  • MÁS
  • diez
  • es
  • diez

Spanish can express equations in more than one natural way.

With your sentence, Spanish uses es:

• Cero más diez es diez

But you can also hear:

• Cero más diez es igual a diez
• Cero más diez igual a diez in some classroom or symbolic reading contexts

So Spanish does not always need a separate word for equals. Using es is very common and natural in simple math statements.

No. When numbers are used by themselves in math, you normally do not use an article.

So you say:

• cero
• diez
• cero más diez

not:

• el cero más el diez

Adding articles would sound unnatural in a basic arithmetic sentence like this.

Because Spanish numbers usually do not change form in basic math expressions.

So:

• cero stays cero
• diez stays diez

Unlike adjectives, these numbers are just being named as mathematical values, so they do not change for gender or number here.

Not if you want to clearly say 0 + 10 = 10.

In math:

• más = plus
• menos = minus
• por = times
• dividido entre / dividido por = divided by

Y usually means and, not plus.

That said, in some very traditional arithmetic phrasing, you may hear things like:

• Dos y dos son cuatro

But for a clear beginner-friendly math sentence, más is the best choice:

• Cero más diez es diez

Yes. The word order is very straightforward and natural:

• cero = zero
• más = plus
• diez = ten
• es = is / equals
• diez = ten

So Spanish follows the same basic order as English here:

• Zero + ten = ten
• Cero más diez es diez

Mostly, it sounds like a math statement or something said while teaching numbers and arithmetic.

It is grammatically correct, but in everyday conversation people usually would not say this unless they are:

• teaching math
• explaining numbers to a child
• practicing Spanish
• reading an equation aloud

So it is a natural sentence, but mainly in a math or learning context.

The sentence is actually very beginner-friendly. The main points are:

• más means plus and needs an accent
• es comes from ser
• Spanish does not need a separate equals
• the numbers stay in their basic form
• the word order is similar to English

So the sentence is simple, but it teaches an important pattern:

• [number] + [number] = [result]
• [number] más [number] es [result]

For example:

• Uno más uno es dos
• Tres más cuatro es siete
• Ocho más dos es diez