Respuesta :

Answer:

[tex]\huge\boxed{\sf x - 3 }[/tex]

Step-by-step explanation:

Let the certain number be x

So,

Given condition:

Sum is to add so we'll use the sign +

= x + (-3)

We know that + and - makes - because - sign will flip the + sign and make it negative, So:

= x - 3

[tex]\rule[225]{225}{2}[/tex]

Solution: c-3

[tex]\searrow[/tex]

Detailed explanation:

[tex]\searrow[/tex]

This problem tells us to convert the verbal phrase (in words) "the sum of a certain number and -3" into an algebraic expression, which is written in numbers.

Let's start by taking a look at our problem.

"the sum of a certain number and -3". We can first write this "certain number" as one letter (any letter you want). Let it be c.

Our expression already looks a little easier: "the sum of c and -3".

Now, the word "sum" tells us to add. So we should add c and -3.

[tex]--\mapsto\boldsymbol{c+-3}[/tex]

Which is the exact same thing as [tex]\boldsymbol{c-3}[/tex].

Voila! There's our answer.

Cheers!! ^-^

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Hope I helped! Best wishes.

Reach far. Aim high. Dream big.

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