Question 156680
-3 < x < 4
a < x + 4 < b


a=?
b=!


Simply take -3 < x < 4 and add 4 to all three "sides".


-3+4 < x+4 < 4+4


Simplify
1 < x+4 < 8


a < x+4 < b


Which numbers take the place of a and b? 1 and 8.  Therefore:
a=1
b=8