SOLUTION: when the children in a school were arranged for a mass drill in equal rows . there were 5 rows more than the children in each row. if the roll call that day was 750. find the numbe

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Question 1073712: when the children in a school were arranged for a mass drill in equal rows . there were 5 rows more than the children in each row. if the roll call that day was 750. find the number of rows formed.
Answer by KMST(5328) About Me  (Show Source):
You can put this solution on YOUR website!
THE FIFTH GRADE FACTORER says
750=75%2A10=25%2A3%2A10=25%2A30 .
There were 25 children in each of highlight%2830%29 rows.

THE ALGEBRA STUDENT says
Let x be the number of children in each row.
Then, x%2B5 is the number of rows, and
x%28x%2B5%29=750 is the number of children in school that day.
x%5E2%2B5x=750
x%5E2%2B5x-750=0
Using the quadratic formula to solve that quadratic equation,
x+=+%28-5+%2B-+sqrt%28+5%5E2-4%2A1%2A%28-750%29+%29%29%2F%282%2A1%29+

The two solutions to that equation are
x=%28-5%2B55%29%2F2=50%2F2=25 and
x=%28-5-55%29%2F2=%28-60%29%2F2=-30 .
Since the number of children in each row cannot be a negative number.
x=-30 is not a solution of the problem, so x=25 ,
and the number of rows is x%2B5=25%2B5=highlight%2830%29 .