pleaseeee tolong yg baik bantuin yaa butuh bgt bantuan.. mksih

a+4 = 4/8 x 12
= 6
a = 2

b+6 = 12/4 x b
= 3b
2b = 6
b = 3

c = 9/6 x 4
= 6

d+8 = 9/6 x 8
= 12
d = 4