## Friday, 13 February 2015

### Algebra... Help! What's Wrong?

Jane did the following:
• 3a + b = 3ab
• 2s + 4t = 6st
Do you think Jane is correct in her algebraic manipulations?
If yes, please write down examples to show that her answer is correct.

If not, explain to Jane her mistakes and help her to correct.

1. No. a and b are two different variables and she cannot create a new varable

2. No. a and b are different variables and ab would be a x b, which is not part of the working.

3. No 3a+b is actually (3xa)+b=3a+b. 2s+4t is (2xs)+(4xt) which is 2s+4t. This is because b,a,s,t are all different variables and cannot be put together as the same type of value.

4. No. a and b are different variables and ab can only be possible in a x b, which is not what Jane did.

5. No. a and b are different values, they cannot be combined into the same equation. The same goes for s and t.

6. No a and b, s and t are different value so she cant add like this and the value is actually 3x(axb) so, what she did was wrong

7. a and b are of different value and she can't just add them both together like that.