Question

sa se rezolve sistemul de ecuatii:
x+y=5
x-y=6

Answer 1

x+y=5
x-y=6

x=5-y
5-y-y=6

x=5-y
-2y=1

y=-0,5
x=5,5

Answer 2

x+y=5
x-y=6

se aduna cele e ecuatii

2x=5+6

x=11/2
y=5-x
y=5-11/2
y=-1/2

verificare
x-y=6
11/2+1/2=12/2=6

deci x=11/2  si y= - 1/2