Answer:
the cost of brand x dog food is $2
Step-by-step explanation:
Let brand X dog food be represented as A
Let Brand Y dog food be represented as B
3 bags of Brand X dog food and 4 bags of Brand Y dog food costs $18,
3A+4B=18
4 bags of Brand X dog food and 3 bags of Brand Y dog food costs
$17.
4A+3B= 17
Using Elimination method
Multiply
- 3A+4B=18 by coefficient of B in equ ii (3) = 9A+12B=54
- 4A+3B= 17 by coefficient of B in equ i (4) = 16A+12B=68
- subtract equation i from equation ii, since sign is the same in both equations
- 9A+12B-(16A+12B)= 54-68
- open bracket
- 9A+12B-16A-12B= 54-68= -14
- 9A-16A+12B-12B= -14
- -7A= -14
- divide both sides by -7
A = -14/-7= 2
Since the brand X dog food is represented as A
the cost of brand x dog food is $2
