This is how the first one would be done. sorry if it’s a little messy the answer is 9. but try using photomath for the rest. it gives you the answer and explains how to do it
 
        
        
        
Answer:
x=2
Step-by-step explanation:
5x +(3-1) =12
5x +2 =12
5x =12-2
5x =10
x =10÷5
x =2
 
        
             
        
        
        
Division expression for fraction 5/4 for is 4 divided by 4 which is .8
 
        
             
        
        
        
Answer:
Step-by-step explanation:
x
=
0