Answer: all the ones that do not have a negative sign in front easy.
 
        
             
        
        
        
Look at deonomators
assuming that the deonomenators are 5x+15y and 2x+6y
find their LCM
factor
5x+15y=5(x+3y)
2x+6y=2(x+3y)
LCM=10(x+3y)=10x+30y
multiply 2/(5x+15y) by 2/2=4/(10x+30y)
multiply 1/(2x+6y) by 5/5=5/(10x+30y)
if we add them
9/(10x+30y)
        
             
        
        
        
Answer:
 (-3,-20)
Step-by-step explanation:
4 +8x = y ...... equation (1)
6x - y = 2 ........equation(2)
from equation 2
6x - y = 2
6x -(4+8x) =2
6x - 4 + 8x = 2
     +4              +4
6x - 8x = 6
-2x=6
divide by -2
x= -3
put x in equation (1) to solve for y
4 + 8x = y
4+8(-3)=y
4-24=y
-20=y 
y= -20
solution = (-3,-20)
 
        
             
        
        
        
Answer:
12 Pints
Step-by-step explanation:
There are 8 pints (pt) in 1 gallon (gal). This means that 1 pint equals 1/8 gallon.
1.5 x 8
=12
 
        
             
        
        
        
Answer:
35 minutes
Step-by-step explanation:
Take the lastest time and subtract the earliest time
9:45 
9:10
------------
   :35
35 minutes