Question 1106233
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A quadratic equation   ax^2 + bx + c = 0


    - has two real zeroes if and only if the discriminant d = b^2 - 4ac is POSITIVE;

    - has one real zero   if and only if the discriminant d = b^2 - 4ac is ZERO;

    - has NO real zeroes if and only if the discriminant d = b^2 - 4ac is NEGATIVE.


So, for your equation, in order for the condition was satisfied, the discriminant 

(k-5)^2 - 4*(4-5k)  must be equal to zero:


(k-5)^2 - 4*(4-5k) = 0.


It is your equation to find the values of "k".


Simplify and solve it by any method you know.
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