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

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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? Any function ax2 + bx + c = 0, where x is a variable of unknown value. A, b, and c are constants. A and b are referred to as coefficients. Interestingly, a cannot be zero in the equation ax2+bx+c=0. If a=0, then ax2=0, and the equation becomes 0+bx+c=0, or bx+c=0. The equation bx+c=0 is a linear equation, and not a quadratic equation.

Compared to solving a linear equation, solving a quadratic equation is a more complicated task. However, you have this handy-dandy quadratic equation solver. All kidding aside, quadratic equations can be always 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. Here is the quadratic formula:


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 be equal, resulting in one solution for x.

Quadratic equations are important. Quadratic equations are needed to calculate answers to many real-world problems. The contour of a parablolic mirror is one example of an application of quadratic equations.

The quadratic equation calculator on this website uses the quadratic formula to solve your quadratic equations, and this is a reliable and relatively simple way to do it. But there are other ways to solve a quadratic equation, such as completing the square or factoring.

We this quadratic equation solver is useful to you. 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.

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