Question

rezolvati in RxR,prin metoda substitutie,sistemulde ecuati
x+2y=3
0,2x-3,5y=4

Answer 1

$\left \{ {{x+2y=3} \atop {0,2x-3,5y=4}} \right.$ ⇒ $\left \{ {{x=3-2y} \atop {0,2(3-2y)-3,5y}=4} \right.$ ⇒ $\left \{ {{x=3-2y} \atop {0,6-0,4y-3,5y=4}} \right.$ ⇒$\left \{ {{x=3-2y} \atop {-3,9y=4-0,6}} \right.$ ⇒$\left \{ {{x=3-2y} \atop {-3,9y=3,4}} \right.$⇒$\left \{ {{x=3-2y} \atop {y= \frac{3,4}{-3,9}=-1,147 }} \right.$⇒$\left \{ {{x=3-2*(-1,147)} \atop {y=-1,147}} \right.$⇒$\left \{ {{x=5,294} \atop {y=-1,147}} \right.$