Ok the answer is -5 less than 9 which is true lol
Anyways here’s how I got the answer 
-5+7+2x-13 less than 9 
Combine like terms in this case it’s -5 and 2, and the other is 7 and -13 
-5+2= -3
7-13= -6
Ok now that that’s done here’s the next step
-3x-6 less than 9 solve it
-3x-6 < 9
 +6< +6
-3x < 15
Now from there you divide then so 
-3x/3 cancels out, and 15/-3 = -5 
X=-5 
And so -5<9 :) hope this helped!! I will also include a picture of my work (please exult messiness lol)
 
        
        
        
        
Answer:
Distributive property
Step-by-step explanation:
In order to solve this equation we first need to distribute 3 into 2y+5, we use the distributive property to do this. 
 
        
             
        
        
        
Answer:
33 1/3 L of the 40% solution, 16 2/3 L of the 25% solution
Step-by-step explanation:
Set up two equations...
Let x represent the number of Liters of the 40% solution
Let y represent the number of Liters of the 25% solution
We need 50 liters total, so
x + y = 50
and we need the 50 L to be 35% solution, so
0.4x = 0.25y =  0.35(50)  
Solve the first equation for one variable...
x = 50 - y             (subtract y from both sides in equation 1)
Now substitute that value into the second equation...
0.4(50 - y) + 0.25y = 17.5      (x becomes 50 - y, 0.35(50) = 17.5)
Now solve for y...
20 - 0.4y + 0.25y = 17.5
   -0.15y = -2.5
       y = 16.66666667
 
         y = 16 2/3 L
So we need to plug that into the first equation to find 'x'
x + 16 2/3 = 50
x = 50 - 16 2/3
x = 33 1/3