diff --git a/tech/Affine.wiki b/tech/Affine.wiki
index a6e390c..01a7bc7 100644
--- a/tech/Affine.wiki
+++ b/tech/Affine.wiki
@@ -11,3 +11,6 @@ Where x is some number corresponding to a letter, 0-25. a and b are variables.
 To decipher, the formula is of form
 
 f(y) = a^-1(y - b) mod 26
+
+Where y is the ciphertext value, and a^-1 is the modular multiplicative inverse
+of a