A disk cost $3 more than a tape. rolex bought five disks and two tapes. The total cost was $120. what was the price of a disk?

First, I would organize your information into equations. So, the first sentence would be:

d = 3 + t d = disk and t = tape

Second and third sentence would be the equation:

5 d + 2 t = $120

To find the price of the disk, you would follow these steps.

5 (3 + t) + 2 t = 120 substitute d, with the equation that has a total, for

(3 + 2), then solve for t

15 + 5 t + 2 t = 120 distribute

15 + 7 t = 120 add like terms

7 t = 105 subtract from both sides

t = 15 divide from both sides

Then you substitute 15 in the first equation.

d = 3 + t substitute

d = 3 + 15 add

d = 18

So, d = 18 and t = 15. To check this, you just need to substitute the right variables.

1) 18 = 3 + 15

18 = 18

2) 5 (18) + 2 (15) = 120

90 + 30 = 120

120 = 120

When checking, we can see that the correct answer is $18 for the price of the disk.

Answer: $18