Question

Find the solution of x2+5x+5=0,if x is a rational no.

Answer 1

x2 +5x+5=0
b2-4ac = (5)2-4*1*5=D
25-20
5
-b+-root D/2a
-5+root5/2, - 5-root5/2

Answer 2

Answer:

The solution are $x=\frac{-5+\sqrt{5}}{2},\frac{-5-\sqrt{5}}{2}$

Step-by-step explanation:

Given : Quadratic equation -$x^2+5x+5=0$

To find : The solution of quadratic equation?

Solution :

Solving by discriminant method,  

General form - $ax^2+bx+c=0$

$D=b^2-4ac$

Solution is $x=\frac{-b\pm\sqrt{D}}{2a}$

Equation is $x^2+5x+5=0$

where, a=1 , b=5, c=5

$D=b^2-4ac$

$D=(5)^2-4(1)(5)$

$D=25-20$

$D=5$

Solution is $x=\frac{-b\pm\sqrt{D}}{2a}$

$x=\frac{-(5)\pm\sqrt{5}}{2(1)}$

$x=\frac{-5\pm\sqrt{5}}{2}$

$x=\frac{-5+\sqrt{5}}{2},\frac{-5-\sqrt{5}}{2}$

Therefore, The solution are $x=\frac{-5+\sqrt{5}}{2},\frac{-5-\sqrt{5}}{2}$