Question

Resolva
3×+2y=9
5×-4y=16
Alguém ajuda ai prf

Answer 1

Resposta:

$x=\frac{34}{11}=3,09\\\\y=-\frac{3}{22}=-0,136$

Explicação passo a passo:

$3x+2y=9 ==>y=\frac{9-3x}{2}\ (I)\\\\5x-4y=16\ (II)\\\\Substituindo\ (I)\ em\ (II)\ temos:\\\\5x-4\bullet(\frac{9-3x}{2})=16\\\\5x-18+6x=16\\\\5x+6x=16+18\\\\11x=34\\\\x=\frac{34}{11}\\\\x=3,09\\\\\\Substituindo\ o\ valor\ de\ x\ em\ (I),\ obtemos:\\\\y=\frac{9-3(\frac{34}{11})}{2}\\\\y=\frac{9-\frac{102}{11}}{2}\\\\y=\frac{\frac{99-102}{11}}{2}\\\\y=-\frac{3}{11}\bullet\frac{1}{2}\\\\y=-\frac{3}{22}\\\\y=-0,136$