Answer:
-2x^2 + 3x -1
Step-by-step explanation:
y = ax^2 + bx + c
(0,-1):  
 -1 = a(0)^2 + b(0) + c
-1 = 0 + 0 + c
-1 = c
(1,0):
0 = a(1)^2 + b(1) + c
0 = a + b + c
(2,-3):
-3 = a(2)^2 + b(2) + c
-3 = 4a + 2b + c
Replace c with -1
0 = a + b -1
1 = a + b
-3 = 4a + 2b -1
-2 = 4a + 2b
-1 = 2a + b
Solve:
2a + b = -1
-1a - b = -1
a = -2
2a + b = -1
-2a -2b = -2
-b = -3 divide both by -1:  b = 3
a = -2; b = 3; c = -1
y = ax^2 + bx + c or y = -2x^2 +3x -1
 
        
             
        
        
        
A) m=-3
B) n=-17
hope this helps x
would love to have brainliest if it is right :)
        
             
        
        
        
Here is your answer friend
 
        
        
        
Answer:
Step-by-step explanation:
substitute the value of y in the first equation.
7x-3(5x-4)=20
7x-15x+12=20
 -8x=20-12
 x=8/-8
 x= -1
then you substitute the value of x on the y equation to find y 
y=5×-1 -4
y= -5-4
y= -9