Answer:
  
3x + 2x2 + 4 = 5
3x + 2x2 + 4 – 5 = 5 – 5
First be sure that the right side of the equation is 0. In this case, all you need to do is subtract 5 from both sides.
  
3x + 2x2 – 1 = 0
2x2 + 3x – 1 = 0
Simplify, and write the terms with the exponent on the variable in descending order.
  
2x2
+
3x
–
1
=
0
↓
  
↓
  
↓
  
  
ax2
  
bx
  
c
  
  
  
a = 2, b = 3, c = −1
  
Now that the equation is in standard form, you can read the values of a, b, and c from the coefficients and constant. Note that since the constant 1 is subtracted, c must be negative.
Answer
2x2 + 3x – 1 = 0; a = 2, b = 3, c = −1
Step-by-step explanation:
 
        
                    
             
        
        
        
9 sheets of paper I believe 
Have a good day :)
        
             
        
        
        
Answer:
73
Step-by-step explanation:
Since DA is the diameter, this means that you can divide the circle into two half-circles.  You will solve with the right half-circle.  A half-circle has a 180 total degrees.  Add up the values given and solve for x.
(2x) + (7x - 4) + (85) = 180
2x + 7x - 4 + 85 = 180
9x - 4 + 85 = 180
9x + 81 = 180
9x = 99
x = 11
Now that you have the value of x, solve for m∠CZB.
m∠CZB = 7x - 4
m∠CZB = 7(11) - 4
m∠CZB = 77 - 4
m∠CZB = 73