Select the set of equations that represents the following situation: The cost of six CDs and twelve DVDs is $73.26; and the cost of thirteen DVDs and twelve CDs is $140.11. How much do a CD and a DVD cost?
6x + 12y = 73.26; 13x + 12y = 140.11
6x • 12y = 73.26; 12x • 13y = 140.11
6x • 12y = 73.26; 13x • 12y = 140.11
6x + 12y = 73.26; 12x + 13y = 140.11
6x + 12y = 73.26; 13x + 12y = 140.11
6x • 12y = 73.26; 12x • 13y = 140.11
6x • 12y = 73.26; 13x • 12y = 140.11
6x + 12y = 73.26; 12x + 13y = 140.11

6x + 12y = 73.26; 12x + 13y = 140.11

6x + 12y = 73.26.........(i) 12x + 13y = 140.11.....(ii)
Where x is the number of C.D's and y is the number of DVD's
Subtracting (ii) from (i)×2 gives
11y=6.41
→y=$0.58
from (i) x= (73.26−12y)/6
=(73.26−12×0.58)/6 =$11.05
Cost of a CD =$11.05
Cost of a DVD =$0.58
Where x is the number of C.D's and y is the number of DVD's
Subtracting (ii) from (i)×2 gives
11y=6.41
→y=$0.58
from (i) x= (73.26−12y)/6
=(73.26−12×0.58)/6 =$11.05
Cost of a CD =$11.05
Cost of a DVD =$0.58

6x + 12y = 73.26; 12x + 13y = 140.11
Using Simultaneous Equations
CD = $11.04
DVD = $0.58
Using Simultaneous Equations
CD = $11.04
DVD = $0.58