What is the equation of the line in slope-intercept form?

In a circle, a 45° sector has an area of 32π cm2. what is the radius of this circle? 32 cm 12 cm 16 cm 8 cm

X+ y = 5 ; x - y =3 solve using linear combination

How many sides does a regular polygon have if each exterior angle measure is 45 degrees explain your answer, i really don't understand this.