Two consecutive angles of a parallelogram

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Subject: Geometry/ Properties and proportions
Name: Veronica
Who are you: Student

The measures of two consecutive angles of a parallelogram are in the ratio
9:11. Find the measure of each angle.

I don't understand this question and I need it answered as soon as possible
because I have a geometry test tomorrow.
Thank you so much
Veronica

Veronica,

The sum of the measures of two consecutive angles in a parallelogram is 180 degrees. You are told that the ratio of these two angles is 9:11. Since 9 + 11 = 20 the first angle is 9/20 of this sum and the second angle is 11/20 of this sum. Hence the first angle is

9/20 180 = 81 degrees

and the second angle is

11/20 180 = 99 degrees.

Penny

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