If (y - 4)(z - 8) + 9(z - 8) = 0, then which of the following must be true?  Choose the correct choice:
A) y = -4 and z = -3  B) y = -4 or z = 8  C) y = -4 or z = 3  D) y = 1 and z = 3  E) y = 1 or z = 3
factor out:   (z-8)(y-4+9)=0   (z-8) (y+5) = 0   So by checking options we get ,   y = -4 or z = 8.
<result>B</result>
If (y - 4)(z - 8) + 9(z - 8) = 0, then which of the following must be true?