x = -5
x = 10
x + 10 = 0
bc = 750
Correct answer is B
\(x^2 + 15x + 50 = 0\)
\(x^2 + 5x + 10x + 50 = 0\)
\(x(x + 5) + 10(x + 5) = 0\)
\((x + 5)(x + 10) = 0\)
x + 5 = 0 or x + 10 = 0.
Comparing \(x^2 + 15x + 50\) with \(ax^2 + bx + c\), b = 15 and c = 50.
\(\therefore\) bc = 750.