Answer: m = 13 ;)
Step-by-step explanation:
 
        
             
        
        
        
Answer:
B) Aluminum and steel are good conductors of electricity.
Step-by-step explanation:
 
        
             
        
        
        
Child=x
Adult=y
y=3x
5.2x+9.9y=767.8
5.2x+9.9(3x)=767.8
5.2x+29.7x=767.8
34.9x=767.8
x=22
        
             
        
        
        
Area = length *width
A = x²
3x² = (x+10)(x+12)
3x² = x²+10x+12x+120
3x² = x²+22x+120
3x²-3x² = x²+22x+120-3x²
0 = -2x²+22x+120
Factor to solve for x: 
-2(x²-11x-60)
(x+4)(x-15)
x = -4  & x = 15 but we can't have a negative length so we eliminate 4. The length of the square is 15 cm.
        
             
        
        
        
Answer:
Part A:




Part B:


 and
 and 
Step-by-step explanation:
Part A:
The inicial concentration of the lemonade is 50%, and the volume is 4 quarts, and we will add x quarts of a lemonade with a concentration of 100%, so the total volume will be y, and the concentration will be 0.7, so we have that:


Using the value of y from the first equation in the second one, we have:





Part B:
If he shoots a total of ten targets, we can write the equation:

Each stationary target is 2 points, and each moving target is 3 points, so if the total points is 23, we have:

If we subtract the second equation by two times the first one, we have:



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