find out the percentage work the whole total out and then divide it 
 
        
                    
             
        
        
        
240 for # 2 because 6 times 4 times 10 is equal to 240 
I am still working on others
        
             
        
        
        
Given, (9x - 4)(9x + 4) = ax² - b
From algebraic identities:
We know, (a + b)(a - b) = a² - b²
Now, 81x² + 36x - 36x - 16 = ax² - b
81x² - 16 = axis² - b
So ax² = 81x²
a = 81
-b = -16
b = 16
Solution
Therefore, the value of a is 81.
<h2>MyHeritage</h2>