X - 9 = 15
-9 = 15 - x
-9 - 15 = - x
-24 = -x
x = 24
        
                    
             
        
        
        
7 hours later.
If her rate is
6km/hour 
then if we do some simple math
6/1=42/7
In 7 hours Amanda will b finished with the marathon
        
                    
             
        
        
        
Answer:
x=6*sqrt(5)
Step-by-step explanation:
We use Pythagoras' theorem:
x^2 =6^2+(24/2)^2
x^2 =6^2+12^2
x^2 =36+144
x^2=180
x=sqrt(180)
x=sqrt(9*4*5)
x=3*2*sqrt(5)
x=6*sqrt(5)
 
        
             
        
        
        
Answer:
a) x=5
b) x=6
Step-by-step explanation:
a)
3x+7=180-(10x-22)
3x+7=202-10x
13x=195
x=5
b)
11x-3=4x+39
7x=42
x=6
I am so sorry I forgot what the formula names are but these are the correct solutions. It has been a while since I've done Geometry.