SOLUTION: Twice a certain whole number subtracted from 3times the square of the number leaves 133. Find the number

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Question 927523: Twice a certain whole number subtracted from 3times the square of the number leaves 133. Find the number


Found 2 solutions by ewatrrr, MathLover1:
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
Twice a certain whole number subtracted from 3times the square of the number leaves 133.
3n^2 - 2n = 133
3n^2 - 2n - 133 = 0
(3n + 19)(n - 7) = 0
whole number
n = 7

Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!

Twice a certain whole number x: 2x
subtracted from 3times the square of the number:3x%5E2
leaves 133:3x%5E2-2x=133

3x%5E2-2x=133

3x%5E2-2x-133=0

x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+

x+=+%28-%28-2%29+%2B-+sqrt%28+%28-2%29%5E2-4%2A3%2A%28-133%29+%29%29%2F%282%2A3%29+

x+=+%282+%2B-+sqrt%28+4%2B1596+%29%29%2F6+
x+=+%282+%2B-+sqrt%28+1600+%29%29%2F6+

x+=+%282+%2B-+40%29%2F6+
solutions:
x+=+%282+%2B+40%29%2F6+
x+=+42%2F6+
x+=+7+
or
x+=+%282+-+40%29%2F6+
x+=-38%2F6+
x+=+-6.33

since we need a certain whole number, our solution is highlight%28x+=+7%29+