Answer:
Quadrilateral as it is a four-sided ploygon, having 4 edges and corners
A) 4 cm
B) 9 cm x 12 cm
C) 108 cm
1.x^2 +6x - 4 = 6x
X^2 + 6x -4 - 6x = 0
X^2 - 4 = 0
By difference of two squares :
X^2 - 4 = 0 can be written as (x-2) (x+2) = 0
(X-2)=0 therefore x= 2
(X+2)=0 therefore x= -2
2. X^2 - 8x = -6x
X^2 -8x + 6x = 0
X^2 - 2x = 0
X(X-2) = 0
X= 0, X= 2