Answer:
x= 20,1 degrees
Step-by-step explanation:
The sum of the inner angles of a triangle is 180 degrees
So it must be
3x-11+6x-10+x = 180
added up the terms with x
10x -11-10 = 180
added up the terms without x
10x - 21 = 180
added up (21) in the two members of the equation
10x-21+21 = 180+21
10x = 201
divide the two members by 10
x = 20,1 degrees
80 inches or feet.. I think you are suppose to multiply 40x2 sorry if im wrong
8x-36 after you distribute. Divide that by 8 and x=4.5.