Answer:
C. When Helen rents 3 DVDs per month, either service will cost her $22.50 per month.
Explanation:
y = 15.00 + 2.50x
y = 12.00 + 3.50x
When x = 2
y = 15.00 + 2.50x
= 15.00 + 2.50(2)
= 15.00 + 5.00
= 20.000
y = 12.00 + 3.50x
= 12.00 + 3.50(2)
= 12.00 + 7.00
= 20.00
When x= 4
y = 15.00 + 2.50x
=15.00 + 2.50(4)
= 15.00 + 10.00
= 25.00
y = 12.00 + 3.50x
= 12.00 + 3.50(4)
= 12.00 + 14.00
=26.00
When x = 3
y = 15.00 + 2.50x
= 15.00 + 2.50(3)
= 15.00 + 7.50
= 22.50
y = 12.00 + 3.50x
= 12.00 + 3.50(3)
= 12.00 + 10.50
= 22.50
When x = 6
y = 15.00 + 2.50x
= 15.00 + 2.50(6)
= 15.00 + 15.00
= 30.00
y = 12.00 + 3.50x
= 12.00 + 3.50(6)
=12.00 + 21.00
= 33.00
The correct answer:
C. When Helen rents 3 DVDs per month, either service will cost her $22.50 per month.