Step-by-step explanation:
(n-2)×180=3420
180n-360=3420
180n=3420+360
180n=3780
n=3780/180
n=21
that is, the number of sides is 21
to get the size of each exterior angle=
360/21
=17.14°
Answer:
As eq of line passing through 2 points is
y-y1 = (y2-y1)/(x2-x1) ][ x -x1)
where (X1,y1)( x2, y2) denotes points lying on line
substitute (X1 ,y1) by( -1,-2) and (X2,y2) by( 2,4)
y+2 = 6/3 )( x+1)
y+2= 2x +2
y = 2x is required equation