SOLUTION: twice the square of a certain whole number added to 3 times the number gives 90. find the number

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Question 1030013: twice the square of a certain whole number added to 3 times the number gives 90. find the number
Answer by FrankM(1040) About Me  (Show Source):
You can put this solution on YOUR website!
2x^2+3x=90
2x^2+3x-90=0
(2x+15 )(x-6)=0
x = -7.5 or x = 6