Last addition to make this a little easier to follow…
At the end of the day, the ratio is the number shown on the first line, 1.414214. If you know how many blocks long your diagonal wall will be and want orthogonal to match, multiply by that ratio. If you have an orthogonal wall and want to make a matching diagonal, divide by the ratio.
Ah yeah, that would lead to some confusion.
It’s this piece:
2 x X(squared) is not y(squared) / 2 even in this example, the square roots don’t really work that way. Also the formula works even if the numbers for (a) and (b) are not the same. This formula doesn’t really ever resolve to equivalence it’s a ratio.
The ratio is 1.414 to simplify though.
a(squared) + b(squared) = c(squared)
5(squared) + 5(squared) = 7.071067… (squared)
25 + 25 = 50 but the square root of 50 isn’t 5, or 10.
It’s not too important but since I brought it up I figured I would follow through 
