Question

15 a2 - 6ab- 8 a2+ 20 - 5ab - 31 + a2- ab

Answer 1

Hi

As you can only add or substract item of the same nature, you must re organise terms.

so :

A = 15 a2 - 6ab- 8 a2+ 20 - 5ab - 31 + a2- ab

Here I have : " a²" ; "ab" then numbers.

In general, you start with letters with highest exponant. If two letters have the same exponent, use alphabetic order.

let's put order :

A = 15a²-8a²+a² -6ab-5ab -ab+20-31

Now you add or substract item of the same kind :

A = 8a² -12ab - 9

Here I can not do anything else, so calculus is over.

Answer 2

Explanation:

Remove the parentheses: 15a²-6ab+8a²+20+5ab-31+a²-ab Combine like terms: 24a²-2ab-11

Answer: 24a²-2ab-11