Problem: The roots of x(x2+8x+16)(4−x)=0x\left(x^{2}+8 x+16\right)(4-x)=0x(x2+8x+16)(4−x)=0 are
Answer Choices:
A. 000
B. 0,40,40,4
C. 0,4,−40,4,-40,4,−4
D. 0,4,−4,−40,4,-4,-40,4,−4,−4
E. none of these Solution:
Set each factor equal to zero, and solve the three resulting equations. The roots are 0,−4,−40,-4,-40,−4,−4, and 444. (The factor x2+8x+16=(x+4)2x^{2}+8 x+16=(x+4)^{2}x2+8x+16=(x+4)2 has the double root −4-4−4.)