Question 150893
"A designer, attempting to arrange the characters of his artwork in the form of a square grid with equal number of row and columns, found that 24 characters were left out."
:
If x = number of characters in each row
we translate this statement as
x*x + 24
x^2 + 24 = total number of characters
:
"When he tried to add one more row and column, he found that he was short of 25 characters."
:
Now, the number of rows is "x + 1", and the number of columns is "x + 1", so we have
(x + 1)(x + 1) - 25 
FOIL
x^2 + 2x + 1 - 25 = total number of charaters
:
an equation using both statement:

x^2 + 2x + 1 -25 = x^2 + 24

x^2 + 2x -24 = x^2 + 24

x^2 - x^2 + 2x - 24 - 24 = 0

2x - 48 = 0

2x = +48

x = 48/2

x = 24

:

Grid is 24 by 24 which contains 576 character + 24 left out = 600

Grid of 25 by 25 = 625 character so he would have 25 blanks