Question

For how many positive integer values of x is the sum x^2+4x+4 less than 20?

Answer 1

1^2 is 1+4 times 1 is 5 plus 4 is 9
2^2 is 4+4 times 2 is 12 plus 4 is 16
3^2 is 9+ 4 times 3 is 21 XXXXXXX==> 2 times