F.28. 21 and 22 are vertical angles. If mZ1 =(6x + 11) and mZ2 = (10x - 9), find mZ1.mZ1 =
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It is given that angle 1 and angle 2 are vertical angles.
It is known that the vertical angles are congruent.
Therefore it follows:
[tex]\begin{gathered} m\angle1=m\angle2 \\ 6x+11=10x-9 \\ 11+9=10x-6x \\ 20=4x \\ x=5 \end{gathered}[/tex]So the value of angle 1 is given by:
[tex]\begin{gathered} \angle1=6x+11 \\ =6\times5+11 \\ =41 \end{gathered}[/tex]Hence the angle is 41 degrees.