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Pls help I have a final in this number 5

Pls help I have a final in this number 5-example-1
User Xxxception
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1 Answer

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To answer this question we will set and solve equations.

1) Notice that the angles that measure 2x+18 degrees and 3x-7 degrees are vertical angles. Since the lines with the marks are parallel, then:


2x+18^(\circ)=3x-7^(\circ).

Adding 7degrees-2x to the above result we get:


\begin{gathered} 2x+18^(\circ)+7^(\circ)-2x=3x-7^(\circ)+7^(\circ)-2x, \\ 25^(\circ)=x. \end{gathered}

2) Notice that the angles that measure 78 degrees and y+10 degrees are corresponding angles. Since the lines with the marks are parallel, then:


78^(\circ)=y+10^(\circ).

Subtracting 10 degrees from the above result we get:


\begin{gathered} 78^(\circ)-10^(\circ)=y+10^(\circ)-10^(\circ), \\ 68^(\circ)=y. \end{gathered}

3) Recall that the interior angles of a triangle add up to 180 degrees, therefore:


y+10^(\circ)+3x-7^(\circ)+d=180^(\circ).

Substituting the above result we get:


68^(\circ)+10^(\circ)+3(25^(\circ))-7^(\circ)+d=180^(\circ).

Simplifying the above result we get:


146^(\circ)+d=180^(\circ).

Therefore:


d=34^(\circ).

Answer:


\begin{gathered} x=25^(\circ),\text{ vertical angles.} \\ y=68^(\circ),\text{ corresponding angles.} \\ d=34^(\circ),\text{ interior angles of a triangle add up to }180^(\circ). \end{gathered}

User WebDrive
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