Lacey, because you have to do the opposite when you want to get rid of a number. She subtracted 20 because it was originally positive 20. Chris messed up and did not do the opposite, subtraction, and instead he added 20
Answer:
2b^2
Step-by-step explanation:
according to the question equation is
(a^2 + b^2 ) - (a^2 - b^2)
a^2 + b^2 - a^2 + b^2
plus a square and minus a square gets cancel
b^2 + b^2
since they are like terms they can be added
2b^2
What is the word problem?
1. 15 Km
2. 17
3. 585.2
4. 243 dollars
