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44 votes
44 votes
A and _B are supplementary angles. If m_A = (4x - 16) and m B = (8x + 4), then find the measure of ZA.

User Jenny Mok
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1 Answer

23 votes
23 votes

A=48

Step-by-step explanation

Two Angles are Supplementary when they add up to 180 degrees

Step 1

if A and B are supplementary angles, then


A+B=180

Let

A=4x-16

B=8x+4

Step 2

replace,


\begin{gathered} A+B=180 \\ 4x-16+8x+4=180 \\ 12x-12=180 \end{gathered}

Step 3

solve for x


\begin{gathered} 12x-12=180 \\ 12x=180+12 \\ 12x=192 \\ x=(192)/(12) \\ x=16 \\ \end{gathered}

Step 4

finally, replace the value of x= 16 to find A


\begin{gathered} A=4x-16 \\ A=4(16)-16 \\ A=64-16 \\ A=48 \end{gathered}

User Bugsyb
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