Geometry!

About 300 bc greeks mathematician euclidge gathered what man knows as geometry . He arendy 465 proposition in to three books called elancmonts. Algebray trigonometry and aduaced arithmetic were in these books. The books also had planc and soild geometry.

!ANGLES!

Acute is an angle that is less then 90 degrees.

Right is an angle that is 90 degees.

Obtuse is an angle that is more then 90 degrees

Straight angle is 180 degrees.

To make a angle you have two lines at a degrees then you have a vertex.