1998 AJHSME Problems/Problem 2

Problem

If $\begin{tabular}{r|l}a&b \\ \hline c&d\end{tabular} = \text{a}\cdot \text{d} - \text{b}\cdot \text{c}$, what is the value of $\begin{tabular}{r|l}3&4 \\ \hline 1&2\end{tabular}$?

$\text{(A)}\ -2 \qquad \text{(B)}\ -1 \qquad \text{(C)}\ 0 \qquad \text{(D)}\ 1 \qquad \text{(E)}\ 2$

Solution

Plugging in values for $a$, $b$, $c$, and $d$, we get

$a=3$, $b=4$, $c=1$, $d=2$,

$a\timesd=3\times2=6$ (Error compiling LaTeX. Unknown error_msg)

$b\timesc=4\times1=4$ (Error compiling LaTeX. Unknown error_msg)

$6-4=2$

$\boxed{E}$

See also

1998 AJHSME (ProblemsAnswer KeyResources)
Preceded by
Problem 1
Followed by
Problem 3
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All AJHSME/AMC 8 Problems and Solutions

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