Math Help!?

Question

If 1/X = x+1 / 1, and x can't equal 0, then, to the nearest thousandth, what is the positive value of x?

Answer 1

If x can't equal 0, then cross multiply to solve this:

1/x = (x + 1) / 1
1 = x(x + 1)
1 = x^2 + x
0 = x^2 + x - 1

Then use the quadratic formula to find x:
x = [-b +/- sqrt(b^2 - 4ac)] / 2a
x = [-1 +/- sqrt((1)^2 - 4(1)(-1))] / 2(1)
x = [-1 +/- sqrt(1 + 4)] / 2
x = [-1 +/- sqrt(5)] / 2
x = [-1+/- 2.236] / 2
x = 0.618, -1.618

Since you're looking for positive x, x = 0.618.