how do I do this? I'm confused.
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Step-by-step explanation:
[tex]\huge\mathcal\blue{here's \: your \: solution} \\ \\ x = 2y - 14 \: \: \: (given) \\ \\ equation \: = 5x - 7y = - 43 \\ \\ now \: put \: the \: value \: of \: x \: in \: equation \\ \\ 5(2y - 14) - 7y = - 43 \\ \\ 10y - 70 - 7y = - 43 \\ \\ 3y - 70 = - 43 \\ \\ 3y = + 70 - 43 \\ \\ 3y = 27 \\ \\ y = 27 \div 3 \\ \\ y = 9 \\ \\ now \: put \: the \: value \: of \: y \: in \: equation \\ \\ x = (9 \times 2) - 14 \\ \\ x = 18 - 14 \\ \\ x = 4 \\ \\ \huge\mathfrak\red{hope \: it \: helps..}[/tex]