Answer:
Step-by-step explanation:
Eq. 1 )   −5x−3y−9=0
Eq. 2)   4x−18y−54=0
there are two routes to solve this,   Substitution or  elimination,  I'll go for the 2nd one because I can see that the y values are a multiple of each other :)
     6 *( −5x−3y−9=0 )
Eq. 3) -30x -18y =54
subtract Eq. 2 from Eq. 3  :)
-30x -18y =54
<u>-( 4x−18y=54)</u>
-34x = 0
so according to the equations then x =0 but,  that's not really a full answer, so now we should go back and try the other method, substitution, 
then:
-5x = 9 +3y
x = - 9/5 + (-3/5)y
now plug that into Eq. 2
4( - 9/5 + (-3/5)y ) - 18y = 54
-36/5 + (-12/5)y -18y = 54
(-12/5)y - (90/5)y = 54+36/5
-(102/5)*y =270/5+36/5
-(102/5)y = 306/5
y = (-5/102)*(306/5)
y = -306/102
y = -3
then plug in for either equation
-5x-3( -3) = 9
-5x + 9 = 9
-5x = 0
x = 0
now we have the full answer
check it by plugging in both x and y into the 2nd equation
4(0) - 18(-3) = 54
54= 54
this seems good  
 
        
             
        
        
        
Answer:23
Step-by-step explanation:
 
        
                    
             
        
        
        
Answer:
Step-by-step explanation:
<u>Total amount to be paid is the sum of 4 bills:</u>
- 21.47 + 14.43 + 13.27 + 25.37 = $74.54
<u>Divide the total by the number of people:</u>
- 74.54/4 = 18.635 = $18.64 rounded to the nearest cent
If the total to be paid equally, then each person has to pay $18.64
 
        
             
        
        
        
The position of the 7 is in the ten thousandths place.
        
                    
             
        
        
        
Answer: 25% decrease in number of boxes of goods
Step-by-step explanation:
If you want to find a percent of a number you turn the percent into a decimal
Example:
Step 1
25% of 748
Step 2
0.25*748=561