1. ## Simplify

The #2's after the letter s below represent squared. Not sure how to post it so it looks that way. Let me know if im doing this one right please.

9m2 -2mn + 5n2 - 9 (5m2 + 6mn - 8n2)

Step 1: Work whats in parenthesis (multiply)

-9 x 5m2 = -45m2 -9 x 6mn = -54mn -9 x 8n2 = -72n2

leaving: 9m2 - 2mn + 5n2 -45m2 - 54mn - 72n2

Step 2: combine like terms

9m2 + -45m2 = -36m2 -2mn + - 54mn = -56mn 5n2 + 72n2 = 77n2

Mr.H

2. Originally Posted by Mr.Huge
The #2's after the letter s below represent squared. Not sure how to post it so it looks that way. Let me know if im doing this one right please.

9m2 -2mn + 5n2 - 9 (5m2 + 6mn - 8n2)

Step 1: Work whats in parenthesis (multiply)

-9 x 5m2 = -45m2 -9 x 6mn = -54mn -9 x 8n2 = -72n2

leaving: 9m2 - 2mn + 5n2 -45m2 - 54mn - 72n2

Step 2: combine like terms

9m2 + -45m2 = -36m2
-2mn + - 54mn = -56mn
5n2 + 72n2 = 77n2

1. The use of the "=" sign is very unconventional (and mathematically wrong). Better use new lines for separate calculations.

2. All calculations are correct so far - but the last line. I've marked the terms in question in red.

3. Originally Posted by earboth
1. The use of the "=" sign is very unconventional (and mathematically wrong). Better use new lines for separate calculations.

2. All calculations are correct so far - but the last line. I've marked the terms in question in red.
ok thank so it should look like this than

Simplify: 9m2 -2mn + 5n2 - 9 (5m2 + 6mn - 8n2)

Step 1: Step 1: Work whats in parenthesis (multiply)

a) -9 x 5m2 -45m2

b) -9 x 6mn -54mn

c) -9 x 8n2 -72n2

Step 2: combine like terms

a) 9m2 + -45m2 -36m2

b) -2mn + - 54mn -56mn

c) 5n2 + 72n2 + 77n2

Step 3:

Answer -36m2 - 56mn + 77n2

Correct? I used the = previously just to show my work via the posting wouldnt have really done that on paper but i understand what you mean. I just wasnt sure how someone would be reading it on here.

Mr.H

4. ## Preview

In my view, it is advisable to use the preview option before posting.

5. Originally Posted by Mr.Huge
ok thank so it should look like this than

Simplify: 9m2 -2mn + 5n2 - 9 (5m2 + 6mn - 8n2)

...

Answer -36m2 - 56mn + 77n2

Correct? I used the = previously just to show my work via the posting wouldnt have really done that on paper but i understand what you mean. I just wasnt sure how someone would be reading it on here.

Mr.H