What constant will make y^2 + 28y + 16 + k the square of a binomial?
y2 + 28y + 16 + k will be the square of a binomial when:
16 + k = (1/2 * 28)2
16 + k = (14)2
16 + k = 196
k = 180
Check:
y2 + 28y + 16 + 180 = y2 + 28y + 196 = (y - 14)(y - 14) = (y - 14)2
