Question

add (r-7s+2)+(4r+6s)+(s+5)
do i add like terms: (4r^2)+(-2s)+(7)

Answer 1

Do not go too fast. Write out the expressions without parentheses, and THEN add like terms, i.e. the coefficients of like terms.

(r-7s+2)+(4r+6s)+(s+5)
= r -7s + 2 +4r +6s +s +5
= r+4r -7s+6s+s +2+5
= 5r +0s + 7

Can you take it from here?

Answer 2

OK, SO THEN I HAVE 4r^2-2s+7
Is that right???

Answer 3

Sorry, 4r^2-2s+7 is not correct. You will have to read and understand every step in my previous response. If you have questions, post the question of the step that you do not understand.

When you add two like terms, such as 2r+4r, you would add only the coefficients to get 6r. Think of adding together 2 oranges + 2 oranges = 4 oranges.

The coefficient of 1 is usually omitted in algebraic expressions, so
r+4r really means 1r+4r which gives 5r.

Start the problem over, and try to understand every step. Repeat the same process for other groups of like terms to get the answer. Also remember that when the coefficient is 0, such as 0x, we omit the term altogether unless this is the only term.

For example,
4x-2x+y-2x
=4x-2x-2x + y
=0x+y
=y

But
5p-2p-3p
=0p
=0