what is the value of \$x\$ in trapezoid abcd? \$x = 15\$ \\(x = 20\…

QUESTION IMAGE

$what is the value of \$x\$ in trapezoid abcd? \$x = 15\$ \\(x = 20\…$

Question

what is the value of \$x\$ in trapezoid abcd?

\$x = 15\$
\$x = 20\$
\$x = 45\$
\$x = 60\$

Explanation:

Response

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"concepts_used": [
"Trapezoid Properties",
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Identify parallel bases

Using the Trapezoid Properties knowledge point
\[
AB \parallel CD
\]

Apply consecutive interior angles theorem

Using the Consecutive Interior Angles knowledge point
\[
\angle B + \angle D = 180^\circ
\]

Set up the equation

Using the Solving Linear Equations knowledge point
\[
3x + 9x = 180
\]

Solve for x

Using the Solving Linear Equations knowledge point
\[

\begin{aligned} 12x &= 180\\ x &= 15 \end{aligned}

\]
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Answer: