Question

3x²+5xy=–4xy–2x=—3alt="solve simultinously" align="absmiddle" class="latex-formula">
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Answer 1

$xy - 2x = - 3$

$xy = 2x - 3$

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$3 {x}^{2} + 5xy + 4 = 0$

$3 {x}^{2} + 5(2x - 3) + 4 = 0$

$3 {x}^{2} + 10x - 15 + 4 = 0$

$3 {x}^{2} + 10x - 11 = 0$

$delta = {10}^{2} - 4(3)( - 11)$

$delta = 100 + 132$

$delta = 232$

Thus;

$x = \frac{ - 10 + \sqrt{232} }{6} \: \: or \: \: x \frac{ - 10 - \sqrt{232} }{6}$

$x = \frac{ - 10 + 15.23}{6} \: \: or \: \: x = \frac{ - 10 - 15.23}{6}$

$x = \frac{5.23}{6} \: \: or \: \: x = \frac{ - 25.23}{6}$

$x = 0.8716 \: \: or \: \: x = - 4.205$

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If x = 0.8716 then :

$0.8716 \: y = 2(0.8716) - 3$

$0.8716 \: y = 1.7432 - 3$

$0.8716 y= - 1.2568$

$y = \frac{ - 1.2568}{0.8716}$

$y = - 1.4419$

And if x = - 4.205 then :

$- 4.205 \: y = 2( - 4.205) - 3$

$- 4.205 \: y = - 8.410 - 3$

$- 4.205 \: y = - 11.410$

$y = \frac{ - 11.410}{ - 4.205}$

$y = 2.7134$

And we're done

Have a great day ♡