Respuesta :

Answer:

3(x+7)=57

Step-by-step explanation:

3 is being multiplied by "the sum of a number(or x) and 7". So, we write it as 3(x+7). That is equal to 57, so that makes the expression 3(x+7)=57.

-hope it helps

Equivalent expressions are expressions that have the same values.

The expression is [tex]3(x + 7) = 57[/tex] and the number is 12

Represent the number with x.

So, the sum of a number (x) and 7 would be represented as: x + 7

Three times the sum would be represented as: 3(x + 7)

This expression is equivalent to 57.

So, we have:

[tex]3(x + 7) = 57[/tex]

Divide both sides of the equation by 57

[tex]x + 7 = 19[/tex]

Subtract 7 from both sides of the equation

[tex]x + 7 - 7 = 19 - 7[/tex]

[tex]x = 12[/tex]

Hence, the number is 12

Read more about equivalent expressions at:

https://brainly.com/question/2972832