Difference between revisions of "1965 AHSME Problems/Problem 35"

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== Solution ==
 
== Solution ==
  
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<asy>
  
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import geometry;
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point M;
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segment l;
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// Rectangle ABCD
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draw((0,sqrt(5))--(0,0)--(5,0)--(5,sqrt(5))--(0,sqrt(5)));
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dot((0,sqrt(5)));
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label("A", (0,sqrt(5)), NW);
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dot((0,0));
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label("B", (0,0), SW);
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dot((5,0));
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label("C", (5,0), SE);
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dot((5,sqrt(5)));
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label("D", (5, sqrt(5)), NE);
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// Segment AC and point M
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M=(2.5,sqrt(5)/2);
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l=line((0,sqrt(5)),(5,0));
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draw(l);
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dot(M);
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label("M",M,W);
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// Segments AX, CY, and XY
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pair[] x=intersectionpoints(perpendicular(M,l),(0,0)--(5,0));
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pair[] y=intersectionpoints(perpendicular(M,l),(0,sqrt(5))--(5,sqrt(5)));
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dot(x[0]);
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label("X",x[0],SW);
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dot(y[0]);
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label("Y",y[0],NE);
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draw((0,sqrt(5))--x[0]);
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draw((5,0)--y[0]);
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draw(x[0]--y[0]);
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// Right Angle Markers
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markscalefactor=0.025;
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draw(rightanglemark((0,sqrt(5)),M,y[0])); // Angle AMY
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draw(rightanglemark((5,0),M,x[0])); // Angle CMX
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draw(rightanglemark((0,sqrt(5)),(0,0),(5,0))); // Angle ABC
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draw(rightanglemark((0,sqrt(5)), (5,sqrt(5)),(5,0))); // Angle ADC
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// Length Labels
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label("$5$",(2.5,0),S);
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label("$w$",(0,sqrt(5)/2),W);
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</asy>
  
 
<math>\fbox{D}</math>
 
<math>\fbox{D}</math>

Revision as of 13:42, 19 July 2024

Problem

The length of a rectangle is $5$ inches and its width is less than $4$ inches. The rectangle is folded so that two diagonally opposite vertices coincide. If the length of the crease is $\sqrt {6}$, then the width is:

$\textbf{(A)}\ \sqrt {2} \qquad  \textbf{(B) }\ \sqrt {3} \qquad  \textbf{(C) }\ 2 \qquad  \textbf{(D) }\ \sqrt{5}\qquad \textbf{(E) }\ \sqrt{\frac{11}{2}}$

Solution

[asy]  import geometry;  point M; segment l;  // Rectangle ABCD draw((0,sqrt(5))--(0,0)--(5,0)--(5,sqrt(5))--(0,sqrt(5))); dot((0,sqrt(5))); label("A", (0,sqrt(5)), NW); dot((0,0)); label("B", (0,0), SW); dot((5,0)); label("C", (5,0), SE); dot((5,sqrt(5))); label("D", (5, sqrt(5)), NE);  // Segment AC and point M M=(2.5,sqrt(5)/2); l=line((0,sqrt(5)),(5,0)); draw(l); dot(M); label("M",M,W);  // Segments AX, CY, and XY pair[] x=intersectionpoints(perpendicular(M,l),(0,0)--(5,0)); pair[] y=intersectionpoints(perpendicular(M,l),(0,sqrt(5))--(5,sqrt(5))); dot(x[0]); label("X",x[0],SW); dot(y[0]); label("Y",y[0],NE); draw((0,sqrt(5))--x[0]); draw((5,0)--y[0]); draw(x[0]--y[0]);  // Right Angle Markers markscalefactor=0.025; draw(rightanglemark((0,sqrt(5)),M,y[0])); // Angle AMY draw(rightanglemark((5,0),M,x[0])); // Angle CMX draw(rightanglemark((0,sqrt(5)),(0,0),(5,0))); // Angle ABC draw(rightanglemark((0,sqrt(5)), (5,sqrt(5)),(5,0))); // Angle ADC  // Length Labels label("$5$",(2.5,0),S); label("$w$",(0,sqrt(5)/2),W);  [/asy]

$\fbox{D}$

See Also

1965 AHSC (ProblemsAnswer KeyResources)
Preceded by
Problem 34
Followed by
Problem 36
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40
All AHSME Problems and Solutions

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