Question 294260
So we have two equations:   r = roses   c= carnations
1) r + c = 17
2) 15r + 8c = 192

Use substitution:  so take equation 1 subtract r from both sides and make it
c = 17 - r   Now sub it into equation 2

15r + 8(17-r) = 192
15r + 136 - 8r = 192
7r + 136 = 192  subtract 136 from both sides
7r = 56 divide by 7
r = 8  now use r = 8 in equation 1

8 + c = 17
c = 9

so you will have 8 dozen roses and 9 dozen carnations