Question

Sum of a number and thrice of its square is 784 find the number

Answer 1

Let number be x
Therefore,
A/q
X + 3x sq = 784
3x2 + x -784 = 0

Solve this quadratic equation

Answer 2

Hi ,
Let the number = x

According to the problem given ,

x + 3x² = 784

3x² + x - 784 = 0

3x² + 49x - 48x - 784 = 0

x ( 3x + 49 ) - 16( 3x + 49 ) = 0

( 3x + 49 ) ( x - 16 ) = 0

3x + 49 = 0 or x - 16 = 0

3x = - 49 or x = 16

x = - 49/3 or x = 16

Therefore ,

Required number = x = 16 or

x = - 49/3

I hope this helps you.


:)