Question

afla necunoscutele x,y,z: x+y=z, y-180=x, x+y=800

Answer 1

y=180+x=> 2x+180=800=>2x=620=> x=310
y=310+180=490
z=490+310=800

Answer 2

x+y=800
y-180+y=800
2y=980
y=490

x+y=z -1-
x+y=800 -2-
Din 1 si 2 rezulta ca z=800

y-180=x
490-180=x
310=x