Respuesta :
Answer:
The cost of one puzzle be $15 .
Step-by-step explanation:
Let us assume that the cost of rock tumblers be x.
Let us assume that the cost of spy pen be y.
Let us assume that the cost of puzzels be z.
Esther purchased two rock tumblers and one spy pen for $74.
Than the equation becomes
2x + y = 74
Eli purchased two puzzles and a spy pen for $50.
Than the equation becomes
y + 2z = 50
Sabine purchased a rock tumbler and two puzzles for $57. Based
Than the equation becomes
x + 2z = 57
Than the three equation are
2x + y = 74
y + 2z = 50
x + 2z = 57
Subtracted y + 2z = 50 from 2x + y = 74 .
2x - y + y - 2z = 74 - 50
2x - 2z = 24
x - z = 12
Now using the equation x - z = 12 and x + 2z = 57 .
Subtracted x - z = 12 from x + 2z = 57 .
x - x + 2z + z = 57 - 12
3z = 45
[tex]z = \frac{45}{3}[/tex]
z = 15
Therefore the cost of one puzzel be $15.
