Simplify the expression 205a − a by combining like terms.

205a^2

204

204a

204a^2

The answer you're looking for is C. 204a.
When you have a variable alone in an equation it will always have an imaginary 1 in front of it.
Ok, so, lets say a stands for Apples, you would subtract one of the Apples from the 205 that you already have and end up with 204 Apples.

(hope this helped :D)

the answer would be c ≈ 18.852*3.14= 6.286.28*3=18.85