The consecutive angles of a particular trapezoid form an arithmetic sequence. If the largest angle measures 140 degrees , what is the measure of the smallest angle?
The sum of all interior angles of a trapezoid==360 degrees
260 - 140 ==220 - sum of the remaining 3 angles.
a+b+c+140 ==360,
140 - c==c - b,
c - b==b - a, solve for a, b, c
a ==40 degrees
b ==220 / 3 ==73 + 1/3 degrees
c ==320 / 3 ==106 + 2/3 degrees.
So, the 4 angles are: 40, 73 1/3, 106 2/3, 140
And the smallest angle ==40 degrees.
