Answer:
She forgot to include a coefficient.
Step-by-step explanation:
[tex]\begin{array}{rcll}(x + 4)(x + 2)(2x+ 1)(x - 2) & = &0 & \text{Correct}\\(x + 4)(2x + 1)(x^{2} - 4) & = &0 &\\(2x^{2} +9x + 4)(x^{2} -4) &= & 0 &\textbf{She forgot the 2 in (2x + 1)}\\2x^{4} +9x^{3} + 4x^{2} -4x^{2} -36x - 16 & = & 0 &\\2x^{4} +9x^{3} -36x - 16 & = & 0 &\\\end{array}[/tex]
Anna forgot to include the coefficient of x in (2x + 1) when she multiplied the two binomials.
