Răspunsuri

Cel mai inteligent răspuns!
2014-07-04T22:31:31+03:00
X+y=23 inmultesc cu 3
3x+3y=69
3x+7y=113
scad cele 2 ecuatii si obtin
7y-3y=113 - 69=44 ⇒ 4y=44⇒ y=44:4=11⇒ x=23-11=12
39 4 39
2014-07-04T23:15:47+03:00
X + y = 23
3x + 7 y = 113
x = 23 - y
3(23 - y) + 7y = 113
69 - 3y + 7 y = 113
4y = 113 - 69
4y = 44
y = 44 : 4
y = 11
x + 11 = 23
x = 23 -11
x = 12
17 4 17