If the square of a positive integer is added to 55 times the integer, the result is 336336. find the integer.

The square of a positive integer added to 4 times the integer is 437 ...

x2 + 4x = 437

I chose to do this by completing the square ...

x2+4x+4 = 437 + 4

(x+2) 2 = 441

Take square root of both sides

x+2 = ±√441

x = - 2 ± 21

x = - 23 or x = 19

x = 19