MathDB

13

Part of 1985 AMC 12/AHSME

Problems(1)

Area of a Quadrilateral

Source:

3/3/2009
Pegs are put in a board 1 1 unit apart both horizontally and vertically. A reubber band is stretched over 4 4 pegs as shown in the figure, forming a quadrilateral. Its area in square units is
[asy] int i,j; for(i=0; i<5; i=i+1) { for(j=0; j<4; j=j+1) { dot((i,j)); }} draw((0,1)--(1,3)--(4,1)--(3,0)--cycle, linewidth(0.7)); [/asy]
<spanclass=′latex−bold′>(A)</span> 4<spanclass=′latex−bold′>(B)</span> 4.5<spanclass=′latex−bold′>(C)</span> 5<spanclass=′latex−bold′>(D)</span> 5.5<spanclass=′latex−bold′>(E)</span> 6 <span class='latex-bold'>(A)</span>\ 4 \qquad <span class='latex-bold'>(B)</span>\ 4.5 \qquad <span class='latex-bold'>(C)</span>\ 5 \qquad <span class='latex-bold'>(D)</span>\ 5.5 \qquad <span class='latex-bold'>(E)</span>\ 6
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