
Phillip R. answered 09/12/14
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write x - 4 as a fraction with denominator = 1
5/x = (x - 4)/1
Now cross multiply
x(x - 4) = 5 multiply out and collect all terms on the left side of the equal sign
x2 - 4x - 5 = 0 factor the quadratic into two binomials
(x - 5)(x + 1) = 0 the product of two numbers = 0 when either number is zero
Therefore x = 5 or x = -1