SOLUTION: An apple orchard that contains 90 trees. The number of trees in each row is 3 more than twice the number of rows. Find the number of rows and the number of trees per row. can you s
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Question 339751: An apple orchard that contains 90 trees. The number of trees in each row is 3 more than twice the number of rows. Find the number of rows and the number of trees per row. can you show me how to set this problem up.Thanks. Answer by ankor@dixie-net.com(22740) (Show Source):
You can put this solution on YOUR website! An apple orchard that contains 90 trees.
The number of trees in each row is 3 more than twice the number of rows.
Find the number of rows and the number of trees per row
:
Let r = number of rows
Let n = number in each row
Then
r * n = 90
:
It also says,"The number of trees in each row is 3 more than twice the number of rows."
the equation for this statement:
n = 2r + 3
:
In the 1st equation, replace n with (2r+3) and you have
r*(2r+3) = 90
2r^2 + 3r = 90
2r^2 + 3r - 90 = 0; a quadratic equation
Factors to
(2r + 15)(r - 6) = 0
the positive solution is all we want here
r = 6 rows
then
n =
n = 15 in each row
:
:
Confirm this with n = 2r + 3
15 = 2(6) + 3
