Solve the linear system using substitution:
\[-x+\frac{ 2 }{ 9 }y=1\] \[9x+3y=6\] I've been trying to solve this for a while now, but can't seem to get the answer, please help!
Multiply each term in the first equation by 9. Then add both of the equations together. This will eliminate the x variable. You can then solve for y. OR Solve one of the equations for y. Then substitute the expression for y that you just found into the other equation. OR Solve one of the equations for x. Then substitute the expression for x that you just found into the other equation. AND View this playlist for examples on how to solve those types of problems. https://www.youtube.com/playlist?list=PLsX0tNIJwRTwHqLbfCQTZdVUmqz1KBHgv I hope this helps.
To solve lets change the second equation into slope-intercept form.... First we would subtract by 9x to get it to the other side... \(\LARGE{(9x-9x)+3y=-9x+6 \rightarrow 3x=-9x+6}\) Next we would divide by 3 to isolate y.... \(\huge{\frac{3y}{3}=\frac{-9x}{3}+\frac{6}{3}}\) What would that equal?
\[y=-3+2\]
Your missing the x where the 3 is so it would be...but Correct :) \(\huge{y=-3x+2}\) Now we know the equation for y...we can now input y into the first equation... \(\huge{-x+\frac{2}{9}(-3x+2)=1}\) In which we would simplify.
oh right, I forgot the x my bad
All's good just make sure to remember next time ;)
So now we solve the equation above...we would first distribute \(\Large{\frac{2}{9}}\) into the equation in parenthesis.... \(\huge{-x+((-3 \times \frac{2}{9})x+(2 \times \frac{2}{9}))=1}\) What would that equal?
\[-x-\frac{ 6 }{ 9 }x+\frac{ 4 }{ 9 }=1\]
Close but not quite. You need to simplify the fraction... \(\huge{-x-\frac{2}{3}x+\frac{4}{9}=1}\) Next combine like terms....
What would.. \(\huge{-x-\frac{2}{3}x=?}\)
\[-\frac{ 5 }{ 3 }x\] ?
Correct :) \(\huge{-\frac{5}{3}x+\frac{4}{9}=1}\) Now we need to get the real numbers to one side so we would subtract \(\Large{\frac{4}{9}}\) on both sides... \(\huge{-\frac{5}{3}x(\frac{4}{9}-\frac{4}{9})=1-\frac{4}{9}}\) What does that simplify too?
\[-\frac{ 5 }{ 9 }x=\frac{ 5 }{ 9 }\]
Correct :) except the fraction with the variable will stay as `-5/3x`.... Now we would isolate the variable by dividing `-5/3`.... \(\huge{(-\frac{5}{3}\div \frac{5}{3})x=\frac{5}{9} \div \frac{5}{3}}\)
oh ugh im sorry I forgot that too
What do you mean?
I forgot that it was 5/3 and not 5/9
Ooo yea...all's good though :)
anyways \[x=\frac{ 1 }{ 3 }\] ?
Correct :) Though I forgot to put a negative sign by `5/3` so that was my mistake so.... \(\LARGE{x=-\frac{1}{3}}\) This is the x-value of the answer now we need to find the y-value... Now we would input x into the second equation.... \(\huge{y=-3(-\frac{1}{3})+2}\) Simplify ;)
Were you able to find what y equals?
\[y=3\]
Correct :) So the solution of the linear system is....\(\LARGE{(-\frac{1}{3},3)}\) Nicely done!
Ah okay, thank you!
I was really breaking my head over this, thanks a lot :)
Your very welcome :) If you ever need help in the future and see me on just tag me and Ill come as soon as I can (thats if im not busy) And I dont know if anyone sent you a welcome message when you joined soo.... \(\Huge{\color{red}{\bigstar}\color{blue}{\bigstar}\color{green}{\bigstar}\color{yellow}{\bigstar}\color{orange}{\bigstar}\color{red}{\bigstar}\color{blue}{\bigstar}\color{green}{\bigstar}\color{yellow}{\bigstar}\color{orange}{\bigstar}\color{red}{\bigstar}\color{blue}{\bigstar}\color{green}{\bigstar}\color{yellow}{\bigstar}}\\\color{white}{.}\\\Huge\sf\color{blue}{~~~~Welcome~to~OpenStudy!~\ddot\smile}\\\color{white}{.}\\\\\Huge{\color{red}{\bigstar}\color{blue}{\bigstar}\color{green}{\bigstar}\color{yellow}{\bigstar}\color{orange}{\bigstar}\color{red}{\bigstar}\color{blue}{\bigstar}\color{green}{\bigstar}\color{yellow}{\bigstar}\color{orange}{\bigstar}\color{red}{\bigstar}\color{blue}{\bigstar}\color{green}{\bigstar}\color{yellow}{\bigstar}}\) \(\Large{By:thomaster}\) Welcome to Openstudy! And I hope you will enjoy this helpful site! ^^ Please check out the code of conduct to learn the rules of this site xD http://openstudy.com/code-of-conduct
Oh no one had haha, thank you!
:)
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