Question

Sistema de equação
{x+y=4
{x²+y²=40

Answer 1

$\left \{ {{x+y=4} \atop {x^{2}+y^{2}=40}} \right.$

x=4-y

(4-y)²+y²=40

16+y²+y²=40

16+2y²=40

2y²=40-16

2y²=24

y²=24/2

y²=12
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x²+y²=40

x²+12=40

x²=40-12

x²=28
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$x=\sqrt{28}$

$y=\sqrt{12}$