Question

Could somebody help me with this please? i forgot how to do these.

Answer 1

Since a full circle has 360degrees and this circle only has two angles, subtract the arc of the known angle to find the arc of the unknown angle.

Angle DGF + angle DEF= 360degrees

Angle DGF + 70degrees= 360 degrees

Angle DGF = 290 degrees

The arc of the unknown angle is 290 degrees