Answer:
-2x³ + x² - 3x - 15
Step-by-step explanation:
Simply combine like terms together:
-5x² - 3x - 7 - 2x³ + 6x² - 8
-2x³ + (-5x² + 6x²) - 3x + (-7 - 8)
-2x³ + x² - 3x + (-7 - 8)
-2x³ + x² - 3x - 15
 
        
                    
             
        
        
        
Answer:
Step-by-step explanation:
 
        
             
        
        
        
-15 why cause ehe had 30 dollars and he first soent 20 such equals to 10 then he soends 25 such equals to -15
        
                    
             
        
        
        
Answer:
I am so sorry :(
Step-by-step explanation:
I would really love to help you, but i am only in the 6th grade and i do not understand this. Hope someone helps you though :)
 
        
             
        
        
        
What should we find... 
Probably base and the height... 
Area = 1440cm²
base = 5×height 
base = 5h
Area of triangle = base × height 
1440 = 1/2 × 5h × h
1440 = 5h²/2
5h² = 2880
h² = 2880/5
h² = 576
h=24cm..
Height = 24cm
Since base = 5h
Base = 5×24
Base = 120cm...
Hope this helped.... 
Base =