Lets review a very simple arithmetic problem that is applicable to Trig.  4 = 12/3

If you remember from elementary school you proved that 4 = 12/3 by multiplying 4 x 3 and if the answer is 12 then you divided correctly.

This procedure is used to solve the following trig problem.

We want to find the hight of side x which is called the side opposite the vertex of 30 degrees.
The tangent of 30o = the side opposite divided by the adjacent side. Hence in this case tan 30o =  x/60
We can solve this problem by using the above arithmetic procedure used to prove 4 = 12/3.
60(tan 30o) = x Remember that tan 30o= 1/√3 therefore we can substitute 1/√3 for tan 30o
and we have 60(1/√3) = x

Therefore x = 60/√3.  and hence x = 34.64 (rounded off) Is this 34.64 measured in feet, meters, km? What determines the measurement?  answer

Using a trig function, determine how long the hypotenuse is?  answer

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