3000000=1.55x^2-5.1x+197

Solution for 3000000=1.55x^2-5.1x+197 equation:

Simplifying
3000000 = 1.55x2 + -5.1x + 197

Reorder the terms:
3000000 = 197 + -5.1x + 1.55x2

Solving
3000000 = 197 + -5.1x + 1.55x2

Solving for variable 'x'.

Combine like terms: 3000000 + -197 = 2999803
2999803 + 5.1x + -1.55x2 = 197 + -5.1x + 1.55x2 + -197 + 5.1x + -1.55x2

Reorder the terms:
2999803 + 5.1x + -1.55x2 = 197 + -197 + -5.1x + 5.1x + 1.55x2 + -1.55x2

Combine like terms: 197 + -197 = 0
2999803 + 5.1x + -1.55x2 = 0 + -5.1x + 5.1x + 1.55x2 + -1.55x2
2999803 + 5.1x + -1.55x2 = -5.1x + 5.1x + 1.55x2 + -1.55x2

Combine like terms: -5.1x + 5.1x = 0.0
2999803 + 5.1x + -1.55x2 = 0.0 + 1.55x2 + -1.55x2
2999803 + 5.1x + -1.55x2 = 1.55x2 + -1.55x2

Combine like terms: 1.55x2 + -1.55x2 = 0.00
2999803 + 5.1x + -1.55x2 = 0.00

Begin completing the square.  Divide all terms by
-1.55 the coefficient of the squared term: 

Divide each side by '-1.55'.
-1935356.774 + -3.290322581x + x2 = 0

Move the constant term to the right:

Add '1935356.774' to each side of the equation.
-1935356.774 + -3.290322581x + 1935356.774 + x2 = 0 + 1935356.774

Reorder the terms:
-1935356.774 + 1935356.774 + -3.290322581x + x2 = 0 + 1935356.774

Combine like terms: -1935356.774 + 1935356.774 = 0.000
0.000 + -3.290322581x + x2 = 0 + 1935356.774
-3.290322581x + x2 = 0 + 1935356.774

Combine like terms: 0 + 1935356.774 = 1935356.774
-3.290322581x + x2 = 1935356.774

The x term is -3.290322581x.  Take half its coefficient (-1.645161291).
Square it (2.706555673) and add it to both sides.

Add '2.706555673' to each side of the equation.
-3.290322581x + 2.706555673 + x2 = 1935356.774 + 2.706555673

Reorder the terms:
2.706555673 + -3.290322581x + x2 = 1935356.774 + 2.706555673

Combine like terms: 1935356.774 + 2.706555673 = 1935359.480555673
2.706555673 + -3.290322581x + x2 = 1935359.480555673

Factor a perfect square on the left side:
(x + -1.645161291)(x + -1.645161291) = 1935359.480555673

Calculate the square root of the right side: 1391.171980941

Break this problem into two subproblems by setting 
(x + -1.645161291) equal to 1391.171980941 and -1391.171980941.

Subproblem 1
x + -1.645161291 = 1391.171980941

Simplifying
x + -1.645161291 = 1391.171980941

Reorder the terms:
-1.645161291 + x = 1391.171980941

Solving
-1.645161291 + x = 1391.171980941

Solving for variable 'x'.

Move all terms containing x to the left, all other terms to the right.

Add '1.645161291' to each side of the equation.
-1.645161291 + 1.645161291 + x = 1391.171980941 + 1.645161291

Combine like terms: -1.645161291 + 1.645161291 = 0.000000000
0.000000000 + x = 1391.171980941 + 1.645161291
x = 1391.171980941 + 1.645161291

Combine like terms: 1391.171980941 + 1.645161291 = 1392.817142232
x = 1392.817142232

Simplifying
x = 1392.817142232

Subproblem 2
x + -1.645161291 = -1391.171980941

Simplifying
x + -1.645161291 = -1391.171980941

Reorder the terms:
-1.645161291 + x = -1391.171980941

Solving
-1.645161291 + x = -1391.171980941

Solving for variable 'x'.

Move all terms containing x to the left, all other terms to the right.

Add '1.645161291' to each side of the equation.
-1.645161291 + 1.645161291 + x = -1391.171980941 + 1.645161291

Combine like terms: -1.645161291 + 1.645161291 = 0.000000000
0.000000000 + x = -1391.171980941 + 1.645161291
x = -1391.171980941 + 1.645161291

Combine like terms: -1391.171980941 + 1.645161291 = -1389.52681965
x = -1389.52681965

Simplifying
x = -1389.52681965

Solution
The solution to the problem is based on the solutions
from the subproblems.
x = {1392.817142232, -1389.52681965}