Question

solve x^2-6x-15=0 using quadratic equation formula
$x ^{2} - 6x - 15 = 0$
THIS IS THE EQUATION TO BE SOLVED ​

Answer 1

Step-by-step explanation:

roots=3+root24 or 3-root24

Answer 2

Given equation

$\to\tt x^2-6x -15=0$

To find

The value of x a using Quadratic Equation Formula

Formula

$\tt\to x = \dfrac{-b\pm\sqrt{b^2-4ac}}{2a}$

Now Compare with

$\tt\to ax^2+bx+c=0$

we get

$\tt\to a =1,b = -6\:\:and\:\: c= -15$

Now Put the value on formula

$\tt\to x = \dfrac{-(-6)\pm\sqrt{(-6)^2-4\times1\times-15} }{2}$

$\tt\to x = \dfrac{6\pm\sqrt{36+60} }{2}$

$\tt\to x = \dfrac{6\pm\sqrt{96} }{2}$

$\tt\to x = \dfrac{6\pm4\sqrt{6} }{2}$

$\tt\to x = \dfrac{2(3+2\sqrt{6} )}{2} \:\: And\:\: x = \dfrac{2(3-2\sqrt{6} )}{2}$

$\tt\to x = 3+2\sqrt{6} \:\: and\:\:x = 3-2\sqrt{6}$

Answer

$\tt\to x = 3+2\sqrt{6} \:\: and\:\:x = 3-2\sqrt{6}$