3.  Here is a 7/8” diameter HSS jobber drill.

What is the included angle of this drill?

Knowing the size of the included angle, calculate the length of the drill point.

Solution:

step 1.  Included angle = 118 degrees

step 2.  find the triangle

step 3.  label known & needed

step 4.  select trig rule – use TAN

step 5.  tan angle = opp /aadj

            tan 59 = 0.4375 / adj

           adj = 0.2629