Respuesta :

The answer is (3a + 20) and also here variable ' a ' appears only once.

Given,

expression (a - 4) and (4a + 16)

subtracting (a - 4) from (4a + 16), results in

= (4a + 16) - (a - 4)

= 4a + 16 - a + 4

=3a+20

Thus, the answer is (3a + 20) and also here  variable ' a ' appears only once.

To learn more about algebra refer here

https://brainly.com/question/14875605

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