SOLUTION: Goodmorning, I need help with this Solve the system by graphing, addition and substitution methods. 3x + y = –1 9x + 3y = –3 Thank you

Algebra ->  Algebra  -> Coordinate Systems and Linear Equations -> SOLUTION: Goodmorning, I need help with this Solve the system by graphing, addition and substitution methods. 3x + y = –1 9x + 3y = –3 Thank you      Log On

Ad: You enter your algebra equation or inequality - Algebrator solves it step-by-step while providing clear explanations. Free on-line demo .
Ad: Algebrator™ solves your algebra problems and provides step-by-step explanations!
Ad: Algebra Solved!™: algebra software solves algebra homework problems with step-by-step help!

   

Question 88288: Goodmorning, I need help with this
Solve the system by graphing, addition and substitution methods.
3x + y = –1
9x + 3y = –3
Thank you
Answer by rapaljer(4667) About Me  (Show Source):
You can put this solution on YOUR website!
3x + y = –1
9x + 3y = –3


Multiply both sides of the first equation by -3 to eliminate the y terms.
-3*(3x + y) = (-3)*–1
9x + 3y = –3

-9x -3 y = 3
9x + 3y = –3

When you add the equations together you get 0=0, which is ALWAYS TRUE. Any time you get 0=0, it means that the equations actually represent the SAME LINE. The entire line is the solution.

R^2