Can i get simplifying these three questions? ! first question 3a–a+18–a second question (a+3)–(a+2) third question 43+a–2a

1. 3a - 1 + 18 - a

So you can reorder these, as long as they keep the sign in front of them.

3a - a - 1 + 18, you can reorder it to.

And then just add or subtract.

2a + 17

2. (a+3) - (a + 2)

First you want to open the parenthesis.

To do that, check the symbol before the parenthesis.

If it's a minus, reverse the operator inside the parenthesis. If it's a plus, do nothing.

So just,

a + 3 - a - 2

Then reorder again

a - a + 3 - 2

1

3. 43 + a - 2a

Just subtract, a - 2a, to get -a.

So,

43 - a