Hacker News
new
|
past
|
comments
|
ask
|
show
|
jobs
|
submit
login
kalid
on Dec 22, 2015
|
parent
|
context
|
favorite
| on:
BetterExplained: Math Lessons That Explain Concept...
I think I left a palm-print on my forehead when I saw that.
Guidelines
|
FAQ
|
Lists
|
API
|
Security
|
Legal
|
Apply to YC
|
Contact
Search:
