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May I please get help with problems (3), I have tried multiple times to find the correct answers for each of them but still could not get the accurate or at least correct answers

May I please get help with problems (3), I have tried multiple times to find the correct-example-1
User Nebenmir
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1 Answer

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In an isosceles trapezoid, the base angles have the same measure pairwise.

The sum of the interior angles of a quadrilateral is 360º

For the given trapezoid:


\begin{gathered} m\angle A+m\angle B+m\angle C+m\angle D=360 \\ \\ m\angle A=m\angle D \\ m\angle B=m\angle C \end{gathered}

Given angle B has a measure of 110º


m\angle B=m\angle C=110
\begin{gathered} 2m\angle A+2m\angle B=360 \\ \\ 2m\angle A+2(110)=360 \end{gathered}

Use the equation above to find the measure of angle A:


\begin{gathered} 2m\angle A+220=360 \\ 2m\angle A=360-220 \\ 2m\angle A=140 \\ m\angle A=(140)/(2) \\ \\ m\angle A=70 \\ \\ m\angle A=m\angle D=70 \end{gathered}

Then, the measures of missing angles are:


\begin{gathered} m\angle A=70 \\ m\angle C=110 \\ m\angle D=70 \end{gathered}

User Hyperrjas
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