check the picture below.
notice, a function that is decreasing, namely  have a negative slope, doesn't have to be negative.
 
        
                    
             
        
        
        
Answer:9+10 is 19
1+1 is 2 
2+2=4 
9 * 9 is 81
12 * 12= 144
last one not sure 
Step-by-step explanation:
 
        
                    
             
        
        
        
Answer:
The length of b is  .
.
Step by step explanation:
Given information: In ΔABC, ∠A =∠C, ∠B = ß (where ß is an acute angle), and BC = x.
Since two angles are same therefore triangle ABC is an isosceles triangle and side AB and BC are congruent.

According to Law of cosine





Therefore the length of b is  .
.
 
        
             
        
        
        
<span>part A:
Let 
t =  total the liquid in the bottle including lemon juice and water
so t =  lemon juice + water ( w = water, l = lemon juice) so t = l + w
but the bottle has 1 liter of water. and <span>60% lemon juice
</span>contains 60% lemon juice = 0.6, so l = 0.6t and w(water ) = 1 liter
t = l + w
substitute l = 0.6t and w = 1 into t = l + w
now you have equation
t = 0.6t + 1
part B:
from part A, you have equation t = 0.6t +1
solve for t
 t = 0.6t +1
subtract 0.6t on both sides
t - 0.6t = 0.6t - 0.6t + 1
simplify
0.4t = 1
divide both sides by 0.4
0.4t/0.4 = 1/ 0.4
simplify
t = 2.5
2.5 liters is total including lemon juice and water
2.5 - 1(1 liter of water) = 1.5 <span>1 liter of lemon juice</span></span>
        
                    
             
        
        
        
Needed gallons for 18 miles = 1
Needed gallons for 200 miles = (1/18)*200
                                                = 11.11 gallons