Răspunsuri

2014-07-25T00:57:29+03:00
X+y=12
x=12-y
x/7=y/5=40/z
(12-y)/7=y/5
Inmultim pe diagonala si obtinem
(12-y)*5=7*y
60-5y=7y
12y=60
y=60/12=5
x+y=12
x+5=12
x=12-5
x=7
7/7=5/5=40/z =>z=40
pentru ca 1=1=1
1 5 1
2014-07-25T01:00:48+03:00
X/7=  y/5= 40/z   x+y=12

(x+y)/(7+5)= 40/z

12/12=40/z

z=12*40/12

z=40

x/7=y/5= 40/40

x/7=40/40

x/7=1

x=7

y/5=40/40

y/5=1

y=5