On the first day of a conference, 10 rows of 6 chairs are set out in a meeting room. the second day, in the same room, 3x more rows with 5x more chairs are set out. which of the following equations could be used to determine the number of chairs set out in the meeting room on the second day? a. y = (15x^2 + 60) chairs b. y = (15x^2) chairs c. y = (15x^2 + 16) chairs d. y = (15x^2 +68x +60) chairs

For this case, what we should do is write the equation step by step to find the total result.
 We have then:
 first day of a conference:
 10 rows of 6 chairs are set out.
 number of chairs set out: (10) * (6) = 60
 Second day of a conference:
 3x more rows with 5x more chairs are set out.
 number of chairs set out: (3x + 10) * (5x + 6) = 15x ^ 2 + 18x + 50x + 60
 number of chairs set out: 15x ^ 2 + 68x + 60

 
 to determine the number of chairs set out in the meeting room on the second day we use:
 D. y = (15x ^ 2 + 68x +60) chairs