angles set with different degrees. 15, 30, 45, 60, 75 and 90 degree. geometric and mathematical . flat line art .

vector design icon school set geometry angle degree 45 math measure geometric symbol education 15 rotation rotate mathematics 90 sign graphic illustration 30 shape isolated acute mathematical count circular science right measurement 60 circle arrow angular coordinate white 75 line teach architecture different arrows learn trigonometry system protractor mathematic pictogram