.
Let angle = x degrees.
Then the supplementary angle is (180-x) degrees.
The problem says
x = 19*(180-x)
Simplify and solve it
x = 19*180 - 19x
20x = 19*180
x = = 19*9 = 171 degrees.
ANSWER. The angle is 171 degrees. its supplementary angle is 180-171 = 9 degrees.
CHECK. = 19. ! Correct !
Solved.
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