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42 votes
y=4.5x+7.5y=−3.5x−4.5Use substitution to solve the system of questionsA. X=-1.5,y=-0.75B. X=1.5,y=0.75C. X=1.5,y=-0.75D. X=-1.5,y=0.75

User JMelnik
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1 Answer

5 votes
5 votes

\begin{gathered} y=4.5x+7.5 \\ y=-3.5x-4.5 \end{gathered}

To solve the system of equations using substitution we replace the value of y from the first equation into the second equation to find the value of x.


4.5x+7.5=-3.5x-4.5

solve the equation for x


\begin{gathered} 4.5x+3.5x=-4.5-7.5 \\ 8x=-12 \\ x=-(12)/(8) \\ x=-1.5 \end{gathered}

using the value of x in either equation find the value of y


\begin{gathered} y=4.5(-1.5)+7.5 \\ y=-6.75+7.5 \\ y=0.75 \end{gathered}

The solution for the system of equations is:

X= -1,5

y= 0.75

User Patrick Trentin
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