The total possibility that the head and even no on dice appears is 3. and total possible choice are 12 {head ---> (1,2,3,4,5,6) & tail ---> (1,2,3,4,5,6)}. so the probability is 3/12= 1/4.
C: 1/4
180, is the answer because when I had a question like that you have to add
Y-4X =3 ; 2x-3y=21
Y= 3+ 4x
2x -3( 3+4x)= 21
2x- 9- 12x= 21
-10x -9= 21
-10x -9+9= 21+9
-10x = 30
X= 30/-10= -3
Y= 3+4x = 3+ 4* (-3)= 3-12= -9
I believe x is 0 because if we assume y and x are 0 then 0=0 and 0= 5 x 0
