If m and n be the absolute maximum and minimum values of the function f(x)=|x2-7x+10|-5x+27, x∈[-2,14] then m+n is
(2)
y={x2-12x+37,x≤22x-x2+17,2<x<5x2-12x+37,x≥5}
y=ax2+bx+c