Thea expression in simplest form is 10.7a + (−6) . Option D
<h3>What are algebraic expressions?</h3>
Algebraic expressions are expressions that comprise of variables, terms, coefficients and constants.
They are also made up of certain mathematical operations.
Given the expression;
(3 + 16.4a) − (9 + 5.7a)
expand the bracket
3 + 16. 4a - 9 - 5. 7a
collect like terms
16. 4a - 5. 7a - 9 + 3
add or subtract like terms
10. 7a - 6
Thus, the expression in simplest form is 10.7a + (−6) . Option D
Learn more about algebraic expressions here:
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