Respuesta :

The sum of the expression 70a and 21b is equivalent to 7(10a + 3b).

An equation is an expression that is used to show the relationship between two or more variables and numbers.

Given the expression:

7(10a + 3b)

Opening the bracket:

= 70a + 21b

The sum of the expression 70a and 21b is equivalent to 7(10a + 3b).