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5 votes
Solve this system of equations. 3x + 4y = 36 1 8 3*+8 y=

User Theopile
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2 Answers

3 votes

Answer:

x = 96488−(4y/3)

Isolate the variable by dividing each side by factors that don't contain the variable.

y = 72366−(3x/4)

Isolate the variable by dividing each side by factors that don't contain the variable.

User Jonny Asmar
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4 votes

x=4, y=6 or ( 4,6)

1) Let's solve this by making use of the Substitution Method

3x+ 4y = 36

y= -1/2x+8

2) Plugging into the first one the 2nd equation:


\begin{gathered} 3x+4(-(1)/(2)x+8)=36 \\ 3x\text{ -2x+32=36} \\ x+32=36 \\ x=36-32 \\ x=4 \end{gathered}

Note that we combined like terms on the 2nd line

And subtracted 32 from both sides.

2.2) Now we can plug into any of them, x=4


\begin{gathered} y=-(1)/(2)(4)+8 \\ y=-2+8 \\ y=6 \end{gathered}

2.3) Testing those solutions we can write out:


\begin{gathered} (4,6) \\ 6=-(1)/(2)(4)+8 \\ 6=-2+8 \\ 6=6\text{ TRUE} \\ 3x+4y=36 \\ 3(4)+4(6_{})=36 \\ 12+24=36 \\ 36=36\text{ TRUE} \end{gathered}

3) Hence, we can state that the answer is x=4, y=6

User Christian Deger
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