Question

substitutions help again! Did this 4 times different answer every time
3x+2y=23
1/2x-4=y

Answer 1

what does "y" equal in relation to "x" ?

Answer 2

"(1/2)x -4" = "y"

right?

Answer 3

I can see that, I used this as a substitute for y and keep getting different answers.

Answer 4

\[3x+2y=23\]
put in Y
\[3x+2(1/2x-4)\]
distribute the 2*1/2x and 2*-4
\[3x+x-8=23\]
solve

Answer 5

yep, then its the adding thats giving you troubles :)

happens to me alot still on my calculus tests