To add the variables, add the coefficients with same variable. The expression which is equivalent to given expression is [tex]7b+3r[/tex]. The option 2 is the correct option.
Equivalent expression are the expression whose result is equal to the original expression, but the way of representation is different.
Given information-
The expression given in the problem is,
[tex](3b+2r)+(4b+r)[/tex]
Let the resultant expression of the above expression is [tex]x[/tex]. thus,
[tex]x=(3b+2r)+(4b+r)[/tex]
To add the algebraic terms open the brackets first,
[tex]x=3b+2r+4b+r[/tex]
Separate the same variable terms,
[tex]x=3b+4b+2r+r[/tex]
To add the variables, add the coefficients with same variable. Thus,
[tex]x=7b+3r[/tex]
Hence, the expression which is equivalent to given expression is [tex]7b+3r[/tex]. The option 2 is the correct option.
Learn more about the equivalent expression here;
https://brainly.com/question/2972832
