Answer:
8x² - 15y² + xy
Step-by-step explanation:
(4x + 5y) (2x - 3y) + 3xy
multiplying the terms in brackets 
(4x) (2x - 3y) + (5y) (2x - 3y) + 3 xy 
multiplying with each terms inside the bracket 
(4x)(2x) - (4x) (3y) + (5y) (2x) - (5y) (3y) + 3xy
doing the product each of the pair of terms
8x² - 12xy + 10xy - 15y² + 3xy
taking the sum of terms with coefficient "xy"
8x² - 15y² -2xy + 3xy
8x² - 15y² + xy
 
        
             
        
        
        
Your answer is
                       Rad. 6 + Rad. 2
- (Negative)    _______________
                                 4
        
                    
             
        
        
        
Answer:
343 - 64 + 457 Solve then you get your answer 
 
        
             
        
        
        
<h3>
Answer:  400  (choice A)</h3>
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Explanation:
40% + 35% = 75% of the coins were either made before 1940, or made from 1940 to 1980. In other words, 75% of the coins were minted before 1980. This leaves 100% - 75% = 25% of the coins to being minted after 1980.
25% of 1600 = 0.25*1600 = 400 coins were made after 1980
 
        
        
        
of means times so you multiply the fractions
1 x 9 = 9
3 x 16 = 48 (we multiplied numerators and denominators)
9/48 = 3/16 (Simplify by dividing a multiple on both the numerator and denominator