Question 1036328
your equation is 3-5x = square root of 5, presumably.
square both sides of the equation to get (3-5x)^2 = 5
simplify to get 9 - 30x + 25x^2 = 5
subtract 5 from both sides of the equation to get 4 - 30x + 25x^2 = 0
reorder the terms in descending order of degree to get 25x^2 - 20x + 4 = 0
factor this quadratic equation to get x = .1527864045 or x = 1.047213596.
when you replace x, in the original equation of 3 - 5x = sqrt(5), with .1527864045, you get 3 - 5*.1527864045 = 2.236067977, which results in 2.236067977 = 2.236067977 which is true.
when you replace x, in the original expression of 3 - 5x, with 1.047213596, you get 3 - 5 * 1.047213596 = -2.236067978, which results in -2.236067977 = 2.236067977 which is not true.
since sqrt(5) = 2.236067977 only, this means that your solution is x = .1527864045 only.
you need to discard x = 1.047213596 because, even though it is a solution to the quadratic equation of (3 - 5x)^2 = 5, it is not a solution to the original equation of 3 - 5x = sqrt(5.