Difference between revisions of "005 Sample Final A, Question 9"

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<math>\begin{array}{rcl}
 
<math>\begin{array}{rcl}
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-x -1 &=& -4\\
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-x -1 &=& -3\\
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-x & =& -3\\
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-x & =& -2\\
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x&=&3
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x&=&2
 
\end{array}</math>
 
\end{array}</math>
 
|}
 
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! Final Answer:
 
! Final Answer:
 
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|-
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|<math>x = 3,~ y = -1</math>
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|<math>x = 2,~ y = -1</math>
 
|}
 
|}

Revision as of 22:48, 18 May 2015

Question Solve the following system of equations

Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \begin{align} 2x + 3y &= & 1\\ -x + y & = & -3\end{align}}


Step 1:
Add two times the second equation to the first equation. So we are adding Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle -2x + 2y = -6} to the first equation.
This leads to:
Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \begin{array}{rcl} 0 + 5y &=& -5\\ -x + y &=& -3 \end{array}}
Step 2:
This gives us that Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle y = -1.}
Now we just need to find x. So we plug in -1 for y in the second equation.

Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \begin{array}{rcl} -x -1 &=& -3\\ -x & =& -2\\ x&=&2 \end{array}}

Final Answer:
Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle x = 2,~ y = -1}
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