The discount was 85% off.
You get everything you need from factoring the last expression:

The left side is a difference of squares, and we get another difference of squares upon factoring. We end up with

Plug in everything you know and solve for
:

Word | know | Unknown
Language| 12 | x
Total | 180 | 28980
Use cross multiply:
12(28980) = 180(x)
347760 = 180x
347760/180=1932
A crow bar is a bar that help you lift thing up
Measures of angles 2, 3, 4, added equal 180