SOLUTION: Melvin needs to set up 182" chairs in a rectangular pattern for a convention. The number of rows is 19 less than three times the number of chairs in a row. How many rows does he ne

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Question 878153: Melvin needs to set up 182" chairs in a rectangular pattern for a convention. The number of rows is 19 less than three times the number of chairs in a row. How many rows does he need and how many chairs in each row? (Find solutions, rows, and chairs in row)
Rows= 3x-19
Chairs in row= x
So far I have x(3x-19)=3x^2-19x+1820 the solutions I got were 3.167-24 and 3.167+24. Is this correct? If not I need the solutions, rows, and chairs in row.
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
No, you need to have an integer solution.
Let R be the number of rows, C the number of chair in a row.
RC=1820
R=3C-19
Substituting,
%283C-19%29C=1820
3C%5E2-19C-1820=0<-- Your sign on the constant is wrong.
You can factor this equation,
%283C%2B65%29%28C-28%29=0
The negative solution doesn't make sense in this problem.
C-28=0
highlight%28C=28%29
R=1820%2F28
highlight%28R=65%29