Question 2 of 8
What is the missing number in the synthetic division problem below?

\begin{tabular}{rrrc}
\hline
2 & -2 & 3 & 4 \\
& 4 & 4 & 14 \\
\hline
2 & 2 & [tex]$?$[/tex] & 18 \\
\end{tabular}

A. 4
B. -1
C. 2
D. 7



Answer :

Sure, let's walk through the steps to find the missing number in the synthetic division problem.

We start with the initial row of coefficients and the divisor used for synthetic division:
[tex]\[ \begin{array}{cccc} 2 & -2 & 3 & 4 \\ & 4 & 4 & 14 \\ \hline \end{array} \][/tex]

The first number of the bottom row is directly taken from the first number of the top row:
[tex]\[ \begin{array}{cccc} 2 & -2 & 3 & 4 \\ & 4 & 4 & 14 \\ \hline 2 & & & \\ \end{array} \][/tex]

Next, multiply the 2 (from the bottom row) by the divisor (4) and write the result (8) below -2:
[tex]\[ \begin{array}{cccc} 2 & -2 & 3 & 4 \\ & 4 & 8 & 14 \\ \hline 2 & & & \\ \end{array} \][/tex]

Add the numbers in the second column:
[tex]\[ \begin{array}{cccc} 2 & -2 & 3 & 4 \\ & 4 & 8 & 14 \\ \hline 2 & 2 & & \\ \end{array} \][/tex]

Next, multiply the new value (2) by the divisor (4) and write the result (8) below 3:
[tex]\[ \begin{array}{cccc} 2 & -2 & 3 & 4 \\ & 4 & 8 & 8 \\ \hline 2 & 2 & & \\ \end{array} \][/tex]

Add the numbers in the third column:
[tex]\[ \begin{array}{cccc} 2 & -2 & 3 & 4 \\ & 4 & 8 & 8 \\ \hline 2 & 2 & 11 & \\ \end{array} \][/tex]

Now, compare the expected fourth term from the synthetic division setup [tex]\(4\)[/tex] added with [tex]\(14\)[/tex] :
[tex]\[ 3 + 4 = 7 \][/tex]

Thus, the missing number required to keep the synthetic division consistent is:

[tex]\[ 11 - 4 = 7 \][/tex]

So the correctly filled in row should be:
[tex]\[ \begin{array}{cccc} 2 & -2 & 3 & 4 \\ & 4 & 4 & 14 \\ \hline 2 & 2 & 7 & 18 \\ \end{array} \][/tex]

Thus the missing number is [tex]\( \boxed{7} \)[/tex]. Answer choice D is correct.