SOLUTION: Hi my name is Matt and i'm in desperate need of help! In 2 weeks we are having finals at my school and we are currently reviewing all the chapters we have covered. We are now going

Algebra ->  Coordinate Systems and Linear Equations -> SOLUTION: Hi my name is Matt and i'm in desperate need of help! In 2 weeks we are having finals at my school and we are currently reviewing all the chapters we have covered. We are now going      Log On


   

Question 701030: Hi my name is Matt and i'm in desperate need of help! In 2 weeks we are having finals at my school and we are currently reviewing all the chapters we have covered. We are now going over solving systems by substitution.
One of the problems is: y=x+3
y=2x+4

Another is: y=2x+10
y=-2x-6

Found 2 solutions by solver91311, josmiceli:
Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!


If y is equal to x + 3 AND y is equal to 2x + 4, then x + 3 must be equal to 2x + 4.

John

Egw to Beta kai to Sigma
My calculator said it, I believe it, that settles it
The Out Campaign: Scarlet Letter of Atheism

Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
+y+=+x+%2B+3+
+y+=+2x+%2B+4+
By substitution:
+x+%2B+3+=+2x+%2B+4+
Subtract +x+ from both sides
+3+=+x+%2B+4+
Subtract +4+ from both sides
+-1+=+x+
-----------
Plug this result back into either
of the equations
+y+=+x+%2B+3+
+y+=+-1+%2B+3+
+y+=+2+
The solution is ( -1,2 )
Here's the plot of the 2 lines showing
the intersection at ( -1,2 )
+graph%28+400%2C+400%2C+-6%2C+6%2C+-6%2C+6%2C+x+%2B+3%2C+2x+%2B+4+%29+
Hope this helps