What is the factor expression of x2-9x plus 4 equals 0?

Answer 1

That equation can not be factored. It can however be solved for x:

x2 - 9x + 4 = 0

x2 - 9x + 81/4 = 81/4 - 4

(x - 9/2)2 = 81/4 - 16/4

(x - 9/2)2 = 65/4

x - 9/2 = ± √65 / 2

x = (9 ± √65) / 2