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and thus
I hope this helps, In December of 2013 we received this question note Felly
Hi Felly, In a right angled triangle such as triangle $BPC$ above if you select one of the nonright angles, such as angle $BCP$ then the tangent of this angle is the length of the opposite side divided by the length of the adjacent side. Thus in the example above \[\tan\left(BCP\right) = \frac{BP}{CP}\] or \[\tan\left(11.25^o\right) = \frac{s}{w}\] and thus \[s = w \times \tan\left(11.25^o\right)\] What remains is to find the value of $\tan\left(11.25^o\right).$ For this I used my calculator. I input 11.25 and then pressed the button labeled tan. My calculator returned 0.1989... You need to take care that your calculator is in degree mode. To make sure calculate $\tan\left(11.25^o\right).$ If you get 0.1989 then you can proceed with your angle. If you don't get 0.1989 your calculator is probably in radian mode and you need to switch it to degree mode. Write back if you need more assistance,  


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