Question 301273
Let the 3 digit number = 100x + 10y + z
:
"the sum of the square of a three digit number is 26."

Proceed with the next two statements
:
"the difference between tens' and hundreds' digit is equal to the units' digit."
y - x = z
-x + y - z = 0
:
find the number if the sum of the 3 digit no. is equal to 8.
x + y + z = 8
:
Add the two equations, find y
x + y + z = 8
-x +y - z = 0
------------------addition eliminates x and z, find y
2y = 8
y = 4
:
therefore x + z = 4
not many choices, only 4 if you include 0
341 or 143 or 242 or 440
;
Square these numbers and see if the digit adds up to 26
341^2 = 116281, 
143^2 = 20449,
440^2 = 193600
All the above each add up to 19
242^2 = 58564 adds up 28,
None add up to 26 ???