To solve the problem we must know about Like terms.
Like terms
like terms are those terms that are having the same variables, also the variables are of the same order as well.
for example, 25x and 5x are like terms; 30xy and 7xy are like terms, 9x³ and 4x² are not like terms, etc.
Expression
In mathematics, an expression is defined as a set of numbers, variables, and mathematical operations formed according to rules dependent on the context.
The sum of (–2.1x + 3.7) and (5 + 4.9x) is (2.8x + 8.7).
Given to us
What is the sum?
We know that when we want to sum to expressions we need to add like terms.
[tex]\ \ (-2.1x + 3.7)+ (5 + 4.9x)\\\\=-2.1x + 3.7+5 + 4.9x\\\\=-2.1x + 4.9x+ 3.7+5 \\\\= 2.8x+8.7[/tex]
Hence, the sum of (–2.1x + 3.7) and (5 + 4.9x) is (2.8x + 8.7).
Learn more about Like terms:
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