This statement is true.
A pyramidal number tells the number of balls that could be stacked evenly with square bases. If were are looking for the nth pyramidal number, that is a pyramid with a square base that is n by n.
A^2 + b^2 + c^2 - ab - bc - ca = 0
a.a + b.b + c.c = a.b + b.c + c.a
equating term by term:-
a = b
b = c
c = a
Therefore a = b = c
Answer:

Step-by-step explanation:

The Pythagorean theorem is the idea that the sum of the two legs which are both squared is equal to the hypotenuse's length squared.
*<em>look at the image I attached for a better explanation</em>
By looking at the picture, we are missing the leg's length, and by using the Pythagorean theorem, we get the equation

Thus the <u>missing side length is 12 cm</u>
Hope that helps!