Question

Use exterior angles to show that the angle sum of quadrilateral PQRS is 360°.​

Answer 1

Answer:

I don't really know but one triangle is 180 degrees so two added together is 360 degrees...

but ohh I remembered

a=c+d (since a+b=180 and c+d+b=180)

e=g+h (since e+f=180 and g+h+f= 180)

and the fact is that c+d+g+h+b+f=the angle sum of quadrilateral PQRS

a+e+b+f= the angle sum of quadrilateral PQRS (by substitutions)

a+e+b+f=360 (four angles are from one origin so it's 360 degrees )