Question

Select the two values of x that are roots of this equation.
x^2+1=5x
*APEX

Answer 1

b and c Apex answers

Answer 2

`\large\boxed{B.\ x=(5+√(21))/(2),\ C.\ x=(5-√(21))/(2)}`

Explanation:

`\text{Use the quadratic formula:}\\\\ax^2+bx+c=0\\\\x=(-b\pm√(b^2-4ac))/(2a)\\\\================================\\\\\text{We have}:\\\\x^2+1=5x\qquad\text{subtract}\ 5x\ \text{from both sides}\\\\x^2-5x+1=0\\\\a=1,\ b=-5,\ c=1\\\\b^2-4ac=(-5)^2-4(1)(1)=25-4=21\\\\x=(-(-5)\pm√(21))/(2(1))=(5\pm√(21))/(2)`