# HG changeset patch
# User Shlomi Fish
# Date 1326481180 -7200
# Node ID 53713e53ef962a9fb9a94490175ffcb1b1036e81
# Parent 5cf905e5f2258675ac75e6caaa34cd80739b98e1
Add some to 138.
diff --git a/project-euler/138/138-analysis.txt b/project-euler/138/138-analysis.txt
new file mode 100644
--- /dev/null
+++ b/project-euler/138/138-analysis.txt
@@ -0,0 +1,17 @@
+Riddle:
+
+[QUOTE]
+Consider the isosceles triangle with base length, b = 16, and legs, L = 17.
+
+By using the Pythagorean theorem it can be seen that the height of the triangle, h = √(172 − 82) = 15, which is one less than the base length.
+
+With b = 272 and L = 305, we get h = 273, which is one more than the base length, and this is the second smallest isosceles triangle with the property that h = b ± 1.
+
+Find ∑ L for the twelve smallest isosceles triangles for which h = b ± 1 and b, L are positive integers.
+[/QUOTE]
+
+h = b +/- 1.
+
+b/2 = h/2 +/- 1/2.
+
+L = sqrt [ h^2 + (h/2 +/- 1/2)^2 ] = sqrt [ 5/4h^2 + 1/4 +/- h/2 ]