You can put this solution on YOUR website!
Wow, long question!
This question seems a little old, but I'll still answer it.
Your question 5 with substitution
Don't let the 2 x's confuse you.
All you need to do (because you are using substitution) is move one of the x's over and the number without a variable over to take its spot.
- New equation
Take the second equation and substitute!
Plug -7 back into the original equation to get X
Plug (-23,-7) back into your answer to make sure you get the right answer. On homework, I would just check the answer in the book to make sure you got it right, but on tests, I highly reccomend checking.
Your question 7 with elimination
Great! You already have coinciding X terms! All you need to do is get rid of it. How? Add 3 to -3 and you get 0!
Plug -2 back in the original equation to find X
Your 3rd question using elimination
All you have to do is multiply the X or Y values to make them equal.
For X, you can make them both 24 by multiplying the top by 6 and the bottom by 4
For Y, you can make them both 35 by multiplying the top by 5 and the bottom by 7
I'll make the X values 24 because the number is smaller.
Plug -2 for Y to get X
Your question 16 (I reccomend elimination)
Plug 2 in for X to get Y
Hope this all helps!