A = 16x + 4        D = 6x - 18 B = 9 - 72x        E = 9x + 6 C = 12 - 2x F = 42 - 14x

A = 16x + 4  
a = 4(4x+1)   

B = 9 - 72x     
b = 9( 1-8x)  

C = 12 - 2x  
c = 2(6-x)     

D = 6x - 18
d = 6(x-3)

E = 9x + 6
e = 3(3x+2)

F = 42 - 14x
f =14 (3 -x)

A) x = -4 / 16
       = -0.25
B) x = -9 / -72
       = 0.125
C) x = -12/-2
       = 6
D) x = 18 / 6
       = 3 
E) x = -6 / 9
       = [tex] \frac{-6}{9} [/tex] 
F) x = -42 / -14
       = 3