Hello,
(3x²+5x-8)+(5x²-13x-5);
3x²+5x²+5x-13x-8-5;
You add up similar terms, you get it:
(3+5)x²+(5-13)x+(-8-5);
8x²-8x-13
Bye:-)
Firstly you should add the like terms i.e. 5x + x. So The answer will be 6x + 2. If it requires you to factorise then take out the highest common factor i.e. 2. So factorised the answer will be 2(3x + 1).
7? Sorry If I'm wrong, I just did 5x7=35 and I dont get your question.
The subtraction property of equality would be used first to solve the equation because you need to isolate n in order to solve the problem.