Answer:
2a^4+5a^3-6a^2+19a-20
Step-by-step explanation:
(a^2+3a-4)(2a^2-a+5)
2a^4-a^3+5a^2+6a^3-3a^2+15a-8a^2+4a-20
2a^4-a^3+6a^3+5a^2-3a^2-8a^2+15a+4a-20
2a^4+5a^3+2a^2-8a^2+19a-20
2a^4+5a^3-6a^2+19a-20
 
        
             
        
        
        
Answer:
D
Step-by-step explanation:
The midpoint is the average of the 2 endpoints, that is
midpoint =  =
 =  = 2.5 → D
 = 2.5 → D
 
        
             
        
        
        
Answer:
-8
Step-by-step explanation:
(x-3y=136) + (18x+3y=288) We collect both processes to make y's disappear
19x=-152
x=-8