' < ' symbol creates a true sentence when x equals 3 8(3-4x)____7(10-x).
Explanation: 
Given: 
X=3 
8(3-4x)____7 (10-x) 
Solution: 
The given equation can be divided as LHS and RHS , So 
LHS be 8(3-4x) 
RHS be 7 (10-x) 
Substituting x=3 in the LHS we get 
8(3-4(3)) 
8(3-12) 
8(-9) 
-72 
Substituting x=3 in the LHS we get 
7 (10-x) 
7 (10-3) 
7(7) 
49 
Hence -72<49. Thus lesser than relation is used.