Answer:
80=8x Ten years
Step-by-step explanation:
80=8x
80/8=x
x=10
 
        
             
        
        
        
89/100. I hope this helps!
        
             
        
        
        
Answer:
To find your heart rate you would, D.  220 - your age
Step-by-step explanation:
You can calculate your maximum heart rate by subtracting your age from 220. For example, if you're 45 years old, subtract 45 from 220 to get a maximum heart rate of 175. This is the average maximum number of times your heart should beat per minute during exercise
 
        
             
        
        
        
<span>a³-b³=(a-b)(a²+ab+b²)
64x⁶ - 27
64 = 4³, 
x⁶ = (x²)³
27 = 3³
</span>64x⁶ - 27 = 4³(x²)³ -3³ = (4x²)³ -3³.  Now, we can use a formula where a=4x², b=3
(4x²)³ -3³ = (4x² -3)((4x²)² +4x²*3 + 3²) =  (4x² -3)(16x⁴ +12x² + 9) 
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Answer: </span>64x⁶ - 27=  (4x² -3)(16x⁴ +12x² + 9) <span>
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Answer:
x = 2
Step-by-step explanation:
Both equations are equal to y, so they're also equal to each other.  We then set them equal to each other:
x^2 - 2x + 1  =  x^2 + 2x - 7
We now do algebra to isolate x.  Subtract 1 from both sides.
x^2 - 2x  =  x^2 + 2x - 8
Subtract 2x from both sides.
x^2 - 4x  =  x^2 - 8
Subtract x^2 from both sides.
-4x = -8
Divide both sides by -4.
x = 2