MHB What are the solutions if h+k=2016 and the roots of x^2+hx+k=0 are integers?

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To solve for integer roots of the equation x^2 + hx + k = 0 with the condition h + k = 2016, the discriminant must be a perfect square. This means that h^2 - 4k must equal a perfect square, allowing for integer solutions. By substituting k with 2016 - h, the equation can be simplified to h^2 - 4(2016 - h) = m^2 for some integer m. Analyzing this leads to a quadratic in h, which can be solved to find valid pairs of (h, k) that satisfy both conditions. The solutions reveal specific integer pairs that meet the criteria established in the problem.
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$if$ $ h+k=2016$
and all roots of $ x^2+hx+k=0$ are both integers
find its solutions
 
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Albert said:
$if$ $ h+k=2016$
and all roots of $ x^2+hx+k=0$ are both integers
find its solutions

let the roots be - a and - b and |a| <= |b| so we get
$(x+a)(x+b) = x^2+hx + k$
or $x^2 + (a+b) x + ab = x^2 + hx + k$
so $a+ b = h,ab = k$
hence $(1+a)(1+b) = (1+ a + b + ab) = 1 + h + k = 2017$
it is a prime so 1 + a = 1 and 1 + b = 2017 so a = 0 and b = 2016 and roots are 0 and - 2016. h = 2016 and k = 0 one solution
or 1 + a = - 1 and 1+b = - 2017 giving a = -2 and b = - 2018 another solution so 2 solutions
 
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