SOLUTION: how do i solve twice the square of a positive integer is 35 more than 9 times that integer? what will the integer be? will it be 7

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Question 73068: how do i solve twice the square of a positive integer is 35 more than 9 times that integer?
what will the integer be? will it be 7
Answer by Earlsdon(6294) (Show Source):
You can put this solution on YOUR website!
First, see if you can write an equation from the given information.
Let the positive integer be called n.
1) Twice the square of a positive integer...write this as
...is (=) 35 more than 9 times the integer...write this as
Now put it alltogether to get:
Now rearrange this into a quadratic equation so it can be solved:
This quadratic equation can be factored.
Now apply the zero product principle.
and/or
If then so Discard this solution as you want only the positive solution.
so This is the solution you want.
The positive integer is 7
Check:
Twice the square of a positive integer...this is = 98
...is (=) 35 more than 9 times the integer... this is = 98
Neat, huh?