Question 427486
<pre><font face = "consolas" color = "indigo" size = 4><b>

x 1 2  3  4  5
y 2 6 12 20 30 


1 times 1 more than 1, or 2,   is  2
2 times 1 more than 2, or 3,   is  6
3 times 1 more than 3, or 4,   is 12
4 times 1 more than 4, or 5,   is 20
5 times 1 more than 5, or 6,   is 30

So

x times 1 more than x, or x+1, is y

  So                     x(x+1) = y

or       y = x(x+1)
           
Edwin</pre>