Solving Quadratic Equations In Simplest Radical Form

by Andrew McMorgan 53 views

Hey math whizzes! Today, we're diving deep into the world of quadratic equations, specifically tackling how to find their solutions when expressed in the simplest radical form. You know, those equations that look a bit like a puzzle, ax2+bx+c=0ax^2 + bx + c = 0, where aa, bb, and cc are just numbers, and xx is our mystery variable. We're going to break down the process, especially when the answers aren't nice, clean integers, and involve those cool square roots. We'll be using a powerful tool called the quadratic formula, which is basically your secret weapon for solving any quadratic equation. Remember, the quadratic formula looks like this: $x = rac{-b The quadratic formula is a fundamental concept in algebra, offering a universal method to find the roots of any quadratic equation in the form ax2+bx+c=0ax^2 + bx + c = 0. When dealing with quadratic equations, especially those that don't factor easily, the quadratic formula becomes indispensable. The goal here is to present the solutions in their simplest radical form, which means simplifying any square roots as much as possible. This involves pulling out any perfect square factors from under the radical sign. For instance, 12\sqrt{12} simplifies to 232\sqrt{3} because 12=4imes312 = 4 imes 3, and 44 is a perfect square. Our main task is to find the solutions to the specific equation 0=−3x2−4x+50 = -3x^2 - 4x + 5. This equation is already set up in the standard form ax2+bx+c=0ax^2 + bx + c = 0, where a=−3a = -3, b=−4b = -4, and c=5c = 5. Plugging these values into the quadratic formula is our first step. This formula is derived from completing the square on the general quadratic equation and is a cornerstone of algebraic problem-solving. It guarantees that we can find solutions for any quadratic equation, whether they are real or complex. The process of simplifying radicals is also crucial here. A radical expression is in its simplest form when the radicand (the number under the radical sign) has no perfect square factors other than 1, there are no fractions in the radicand, and no radicals appear in the denominator of a fraction. Mastering these simplification techniques ensures that our final answers are presented in the most concise and standardized way possible, which is essential in mathematical contexts and standardized tests. Let's get started with applying the formula to our specific problem and see what we uncover. Understanding the nuances of the quadratic formula and radical simplification will equip you with the skills to tackle a wide range of algebraic challenges. This fundamental knowledge is key to progressing in mathematics, from high school algebra to more advanced calculus and beyond. It's all about building a strong foundation, and quadratic equations are a significant part of that foundation. So, let's gear up and simplify these solutions! The beauty of mathematics lies in its structure and logic, and the quadratic formula is a prime example of elegant mathematical design that solves a common problem type efficiently and effectively.

Applying the Quadratic Formula

Alright guys, let's roll up our sleeves and plug our values into the quadratic formula. Remember, our equation is 0=−3x2−4x+50 = -3x^2 - 4x + 5. From this, we've identified our coefficients: a=−3a = -3, b=−4b = -4, and c=5c = 5. Now, let's substitute these into the formula: x=−b±b2−4ac2ax = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}. Substituting our values, we get: x=−(−4)±(−4)2−4(−3)(5)2(−3)x = \frac{-(-4) \pm \sqrt{(-4)^2 - 4(-3)(5)}}{2(-3)}.

Let's simplify this step-by-step. First, the −b-b part becomes −(−4)-(-4), which is just 44. Next, we look at the term inside the square root, the discriminant: b2−4acb^2 - 4ac. Here, it's (−4)2−4(−3)(5)(-4)^2 - 4(-3)(5). Squaring −4-4 gives us 1616. Then, multiplying −4-4 by −3-3 gives us 1212. And 1212 multiplied by 55 is 6060. So, the expression becomes 16−(−60)16 - (-60), which simplifies to 16+60=7616 + 60 = 76. So, the part under the square root is 7676. Finally, the denominator, 2a2a, is 2(−3)2(-3), which equals −6-6.

Putting it all back together, our expression for xx is now: x=4±76−6x = \frac{4 \pm \sqrt{76}}{-6}.

This is a good start, but we're not quite done yet. The key phrase here is simplest radical form. This means we need to simplify that 76\sqrt{76}. To do this, we look for the largest perfect square that divides 7676. Let's try some perfect squares: 44? Yes, 7676 is divisible by 44. In fact, 76=4×1976 = 4 \times 19. Since 44 is a perfect square (222^2), we can pull it out of the radical. So, 76\sqrt{76} becomes 4×19=4×19=219\sqrt{4 \times 19} = \sqrt{4} \times \sqrt{19} = 2\sqrt{19}.

Now, substitute this simplified radical back into our expression for xx: x=4±219−6x = \frac{4 \pm 2\sqrt{19}}{-6}.

We're almost there! We can simplify this fraction further. Notice that all the numbers in the numerator (44 and 22) and the denominator (−6-6) are divisible by 22. Let's divide each term by 22. This gives us: x=4/2±(219)/2−6/2=2±19−3x = \frac{4/2 \pm (2\sqrt{19})/2}{-6/2} = \frac{2 \pm \sqrt{19}}{-3}.

Typically, we like to have a positive denominator. We can achieve this by multiplying both the numerator and the denominator by −1-1. This flips the sign of every term:

x=−(2±19)−(−3)=−2∓193x = \frac{-(2 \pm \sqrt{19})}{-(-3)} = \frac{-2 \mp \sqrt{19}}{3}.

Wait a minute! The ∓\mp sign means