Mathematics
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Substitution method 1) 3x + y = 7 4x + 2y = 16 2) 2x + 2y = 4 X - 2y = 0

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(2) Answers
maria169

1. y=7-3x 4x+2(7-3x)=16 4x+14-6x=16 -2x=2 x=-1 -3+y=7 y=10 (-1,10) 2. x=2y 2(2y)+2y=4 4y+2y=4 6y=4 y=2/3 x-2(2/3)=0 x-4/3=0 x=4/3 (4/3,2/3)

Jaywise

[latex]1.)\\ \\\begin{cases}3x + y = 7 /*(-2)\\ 4x + 2y = 16 \end{cases} \\ \\\begin{cases}-6x-2y =-14 \\ 4x + 2y = 16 \end{cases}\\-------\\-2x=2/:(-2)\\ \\x=-2[/latex] [latex]3*(-1) + y = 7\\ \\-3+y=7\\ \\y=7+3\\ \\y=10\\ \\\begin{cases}x=-1\\ y=10 \end{cases}[/latex] [latex]2.)\\ \\\begin{cases}2x + 2y = 4 \\x - 2y = 0 \end{cases} \\-------- \\ 3x=4/:3\\ \\x=\frac{4}{3}\\ \\2*\frac{4}{3}+ 2y = 4 \\ \\[/latex] [latex]2y=\frac{12}{3}-\frac{8}{3}\\ \\2y=\frac{4}{3}/*(\frac{1}{2})\\ \\y=\frac{2}{3}\\ \\\begin{cases}x=\frac{4}{3} \\y=\frac{2}{3}\end{cases}[/latex]

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