Distance between stepladder feet with sides 2m and 1.85m at 65°

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Homework Statement


The two sides of a stepladder are of length 2m and 1.85m. When fully opened, the longer side is inclined at 65° to the horizontal. Find the distance apart of the feet of the step ladder.

Homework Equations


Sin Rule & Pythagoras?

The Attempt at a Solution


I had a go but I really think it's wrong.

HomeworkQues.jpg


[itex]\frac{2}{\sin90°} = \frac{b}{\sin65°}[/itex]

[itex]b = \frac{2}{\sin90°}\times \sin65°[/itex]

[itex]b = 1.81 (2d.p.)[/itex]

[itex]a^2 = 2^2 - 1.81^2 = 0.7239[/itex]

[itex]a = 0.85 (2d.p.)[/itex]

[itex]x^2 = 1.85^2 - 0.85^2 = 2.7[/itex]

[itex]x = 1.64 (2d.p.)[/itex]

[itex]l = 1.81 + 1.64 = 3.45m[/itex]


P.S. How do you do new lines in LaTeX?
 
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How do you know that the top angle is 90 degrees when it is fully opened? I think you have to stick with just the 65 degree angle and the leg lengths in order to find the distance.

Also, I don't know how to do new lines in LateX. I always just close the tex tag and start a new one.
 


I thought it would be 90 degrees because it says 65 degree to the horizontal.
 


You can't assume that the ladder opens up at 90 degrees (it doesn't actually).
 


I see what I did wrong. I got horizontal and vertical mixed up so I drew my diagram wrong.