Question 824176
I need more detail solution:

A child has a bag full of little toy bricks each of dimensions 1cm x 1 cm x
1cm and decides to build a little wall with them. He wants to have 2 bricks in the top
row, 4 in the second row from the top, 6 in the third row from the top, and so on,
always placing two more bricks in every row below. If he has a total of 950 little
bricks, how tall can he make his wall?
<pre>
This is an arithmetic progression, with formula: {{{S[n] = (n/2)2a[1] + (n - 1)d}}}. 
Proceed to determine n, or number of rows, with:
{{{S[n]}}} being the sum of the AP, or 950
{{{a[1]}}} being the 1st term, or 2
d being the common difference, or 2

Plugging the variables into the formula should result in the quadratic equation: {{{n^2 + n - 950 = 0}}}
This results in n, or number of rows being 30.822 &#8776; 30

Since each brick is 1 cm high, then height of wall = 30 * 1, or {{{highlight_green(30)}}} cm
You can do the check!! 

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