what is the value of x?
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we know that
An exterior angle is equal to the sum of the two non adjacent angles
so
In this problem
[tex]100\°=x\°+70\°[/tex]
Solve for x
Subtract [tex]70\°[/tex] both sides
[tex]x\°+70\°-70\°=100\°-70\°[/tex]
[tex]x\°=30\°[/tex]
therefore
the answer is the option D
[tex]30\°[/tex]