Two angles of a quadrilateral each measure 70°. A third angle of the quadrilateral measures 115°. What is the measure of the fourth angle of the quadrilateral?

Respuesta :

Quadrilateral's angles add up to 360 degree 
So .....
70+70+115+x=360
255+x=360
x=360-255
x=105 degrees

Hope I didn't mess up for your sake.