Question

the sum of a whole number and twice the square of the number is 10

Answer 1

Solution :

Let the whole number = x

according to the problem given ,

x + 2x² = 10

=> x + 2x² = 10

=> 2x² + x - 10 = 0

=> 2x² + 5x - 4x - 10 = 0

=> x( 2x + 5 )-2( 2x + 5 ) = 0

=> ( 2x + 5 )( x - 2 ) = 0

=> 2x + 5 = 0 or x - 2 = 0

=> x = -5/2 or x = 2

Therefore ,


Required whole number is

x = 2

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