👤
a fost răspuns

Rezolvati prin metoda substitutiei sistemele: sistem: 3/5x+ 1/2y=2 -7x+4y=-43

Răspuns :

Smarianta
 3/5x+2y=2 |*2 => 6x+5y=20 => x=(20-5y)/6
 -7x+4y=-43
=>-7(20-5y)/6+4y=-43 |*6
-140+35y+24y=-258
59y=-118 => y=-2
x=(20+5*2)/6=30/6=5
Renatemambouko
3x/5 +y/2 =2
-7x+4y=-43

6x +5y =20     y=(20-6x)/5
-7x+4y=-43
-7x+4(20-6x)/5=-43
-35x+80-24x=-215
59x=295
x=295/59
x=5
y=(20-6x)/5=(20-6×5)/5=(20-30)/5=-2

x=5
y=-2