Line p is parallel to side BC.

Triangle A B C. Angle A is 2, angle B is 73 degrees, and angle C is 37 degrees. A line p is parallel to side B C at point A to form 3 angles. Angle 2 is angle A, and angle 1 is the exterior angle.

What is the measure of angle 1 in degrees?

hello from mrbilldoesmath!

answer:

a(n) - a(n-1) -3

discussion:

this ones a bit interesting. given a(n) = 5 - 3n consider this:

a(n-1) = 5 - 3(n-1)

          = (5 - 3n) + 3             => but a(n) = 5 - 3n, the first term

          = a(n)   + 3                 => subtract 3 from both sides

a(n-1) -3 = a(n)  

or

a(n) - a(n-1) -3

you,

mrb