A=
B=
Blank 1:
Blank2:

Answer:
a=3,b=1
Step-by-step explanation:
In a parallelogram opposite sides are equal/congruent.
Using this, we know that 3a-4=a+2 and b+1=2b
1st equation:
3a-4=a+2
-a -a
2a-4=2
+4 +4
2a=6
a=3
2nd equation:
b+1=2b
-b -b
b=1
a=3, b=1