How do you solve (x^2+5)/(2x)=5?

1 Answer
Apr 30, 2017

"x_1=5-2sqrt5
x_2=5+2sqrt5

Explanation:

(x^2+5)/(2x)=5

x^2+5=2x*5

x^2+5=10x

x^2-10x+5=0

"This is a quadratic function .We should find the roots of the function."

"if "ax^2+bx+c=0

Delta=sqrt (b^2-4ac)

"Where "a=1" , "b=-10" , "c=5

Delta=sqrt((-10)^2-4*1*5)=sqrt(100-20)=+-sqrt(80)

x_1=(-b-Delta)/(2a)=(10-sqrt 80)/(2*1)=(10-4sqrt5)/2=5-2sqrt5

x_1=(-b+Delta)/(2a)=(10+sqrt 80)/(2*1)=(10+4sqrt5)/2=5+2sqrt5