What is the measure of ∠B? Triangle A B C with ray A G through point C and angle measures A = 3x, B = 4x, and exterior angle B C G = 10x minus 45.

60∘60 degrees

15∘15 degrees

45∘45 degrees

105∘

Step by step explanation pls for 10 pts the length of a rectangular board is 3 feet less than twice its width. a second rectangular board is such that each of its dimensions is the reciprocal of the corresponding dimensions of the first rectangular board. if the perimeter of the second board is one-fifth the perimeter of the first, what is the perimeter of the first rectangular board?