If 12 is added to the square of a positive integer, the result is 133. Find the positive 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 = 441Take square root of both sides x+2 = ±√441x = - 2 ± 21 x = - 23 or x = 19 We are told the variable is a positive integer, x = 19

Check: 192 + 4 (19) = 437 361 + 76 = 437 437 = 437 This answer checks