Robert spent $45 buying songs and movies at an online store that charges 1.75 for each song and $2.50 for each movie he purchased a total of 20 songs and movies combined write a system of equations that represents this situation

x= number of songs bought

y= number of movies bought

1.75*x + 2.5*y = 45

x + y = 20

Step-by-step explanation:

Giving the following information:

Robert spent $45 buying songs and movies at an online store that charges 1.75 for each song and $2.50 for each movie he purchased a total of 20 songs and movies combined.

We need to establish a system of equations that represents this situation.

x= number of songs bought

y= number of movies bought

1.75*x + 2.5*y = 45

x + y = 20

Now, we can determine the x and y:

x= 20 - y

Substitute x:

1.75*(20 - y) + 2.5y = 45

35 - 1.75y + 2.5y = 45

0.75y = 10

y= 13

x= 20 - 13

x= 7

Prove:

1.75*7 + 2.5*13 = 45

7 + 13 = 20

x = -4

step-by-step explanation:

- 20 - 4(x + 3) = 4x

=> -20 - 4x - 12 = 4x

=> - 32 -4x = 4x

=> -32 = 4x + 4x

=> - 32 = 8x

=> -32/8 = x

=> -4 = x

if gloria has "carry over" minutes, (that is, any minutes paid for but not used in a month can be applied to her payment for minutes in the next month,) her total usage for the three months is: total minutes = 320 + 243 + 489 = 1052 minutes number of 200 minute blocks = 1052/200 = 5 r52 (that is 5 with a remainder of 52) rounding up the number of 200 minute blocks gives her usage for the three months as 6 blocks. the cost for six blocks is 6 x $25 = $150 she also has 200 - 52 or 148 carry over minutes if gloria pays each month and unused minutes are lost, applying the rounding up procedure to each month gives: first month usage of 320 minutes rounds up to 2 blocks of 200 minutes for a payment of 2 x $25 = $50 second month usage of 243 minutes rounds up to 2 blocks of 200 minutes for a payment of 2 x $25 = $50 third month usage of 489 minutes rounds up to 3 blocks of 200 minutes for a payment of 3 x $25 = $75 total payments for the three months are $50 + $50 + $75 = $175 get the plan with carry over minutes!