Question

Which property justifies each step in all of these? Of these ten: www.analyzemath.com/algebra/rules_algebra.html

I got all of them wrong and can't find out why

1. 6a + (8b + 2a)
= (6a + 2a) +8b

2. (6a + 2a) + 8b
= (6 + 2)a + 8b

3. (6 + 2)a + 8b
= 8a + 8b

4. 8a2 + (8a + a2) + 7a
= 8a2 + (a2 + 8a) + 7a

Answer 1

<u>all</u> wrong? Man -- there are only about four properties!
#1 Associative: (a+b)+c = a+(b+c)
#2 Distributive: a(b+c) = ab + ac
#3 ditto
#4 Commutative: a+b = b+a

Time to review the section, eh?

Answer 2

Thank you! I see that there's more than four on the list though...

Answer 3

8a2 + (a2 + 8a) + 7a

= (8a2 + a2) + 8a + 7a
what property is this and how do you know?