Question

dau coronita **:
1
stiind ca x+2y=24 si x+y=19,determinati x
2
aflati cifra a,stiind ca :
aaa+aa+a=369
aaa+aa+a=246
3
folosind proprietatea adunarii (asoc. si com.) calculati :1+2+3+97+98+99
21+22+23+77+78+79
4:
suma a 4 nr naturale consecutive este 48 .aflati nr..
suma a 4 nr naturale consecutive este 98 .aflati nr..

Answer 1

1.x+2y=24 x+y=19 x=24-2y 24-2y+y=19 24-y=19 Y=24-19 y=5 x+y=19 x+5=19 x=19-5 x=14