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

A quadratic equation is an equation
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. Additionally, it is worth noting that a cannot equal 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.

Finding a solution to a quadratic equation may seem challenging. However, you have this handy-dandy quadratic equation solver. Acutally, quadratic equations can be readily 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. This is the quadratic formula:


Since there are always 2 solutions to a square root (one negative, one positive), solving the quadratic equation results in 2 values for x. The two solutions for x (which may be positive or negative, real or complex) are called roots. Under extraordinary circumstances, these two roots may equal each other, meaning there will only be one solution for x.

Why do we need to be able to solve quadratic equations? Quadratic equations are needed to find answers to many real-world problems. The acceleration of an object as it falls to earth 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 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.

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