# Solving 66x2+-38x+6 using the Quadratic Formula

For your equation of the form "ax2 + bx + c = 0," enter the values for a, b, and c:

 a x2 + b x + c = 0
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You entered:
66x2+-38x+6=0.

There are no solutions in the real number domain.
There are two complex solutions: x = 0.28787878787879 + 0.089637572471206i, and x = 0.28787878787879 - 0.089637572471206i,
where i is the imaginary unit.

## Here's how we found that solution:

You entered the following equation:
(1)           66x2+-38x+6=0.

For any quadratic equation ax2 + bx + c = 0, one can solve for x using the following equation, which is known as the quadratic formula:
(2)

In the form above, you specified values for the variables a, b, and c. Plugging those values into Eqn. 1, we get:
(3)           $$x=--38\pm\frac{\sqrt{-38^2-4*66*6}}{2*66}$$

which simplifies to:
(4)           $$x=--38\pm\frac{\sqrt{1444-1584}}{132}$$

Now, note that b2-4ac is a negative number. Specifically in our case, 1444 - 1584 = -140.
(5)           $$x=--38\pm\frac{\sqrt{-140}}{132}$$

This means that our solution will require finding the square root of a negative number. There is no real number solution for this, so our solution will be a complex number (that is, it will involve the imaginary number i, defined as the square root of -1.).
Let's calculate the square root:
(6)           $$x=--38\pm\frac{11.832159566199i}{132}$$

This equation further simplifies to:
(7)           $$x=-\frac{--38}{132}\pm0.089637572471206i$$

Solving for x, we find two solutions which are both complex numbers:
x = 0.28787878787879 + 0.089637572471206i
and
x = 0.28787878787879 - 0.089637572471206i

Both of these solutions are complex numbers.
These are the two solutions that will satisfy the equation 66x2+-38x+6=0.

### Notes

What is a quadratic equation? A quadratic equation is any equation that takes the form:
ax2 + bx + c = 0.
\ In this equation, a, b, and c are constants. X is unknown. The constants a and b are called coefficients. It is worth pointing out that a cannot equal zero in the equation ax2+bx+c=0. Otherwise, the equation ceases to be a quadratic equation, and becomes a linear equation.

Solving a linear equation is relatively basic. Solving a quadratic equation requires some more advanced mathematics. However, you have this handy-dandy quadratic equation solver. All kidding aside, quadratic equations can be reliably solved using the quadratic formula, which is the same technique used by this quadratic equation solver. Try it, and it will explain each of the steps to you. The quadratic formula is written:

Solving a quadratic equation will always result in 2 solutions for x. These solutions are called roots. These roots may both be real numbers or, they may both be complex numbers. Rarely, these two roots may equal each other, producing one solution for x.

There are many uses for quadratic equations. Quadratic equations are needed to find answers in many real-world fields, including physics, biology and business.

As mentioned above, in the equation ax2+bx+c=0, a cannot be zero. If a were 0, then ax2 = 0x2 = 0 for any value of x, so our equation becomes 0 + bx + c = 0, which is the same as bx + c = 0, which is no longer a quadratic equation. In fact, bx + c = 0 is a linear equation, which is much simpler to solve than a quadratic equation.

We hope you find this quadratic equation calculator useful. We encourage you to try it with different values, and to read the explanation for how to reach your answer. But, if you just want to use it to calculate the answers to your quadratic equations, that's cool too. Thank you for your interest in Quadratic-Equation-Calculator.com.