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Question

one angle of a quadrilateral is 10 more than 10 times a number x. another angle is 8 more than 8 times that same number x. the third angle is half the fourth angle. the fourth angle is 120 degrees. what is the value of x

Answer 1

The sum of the angles of a quadrilateral is 360°.

Write down the 4 expressions for the angles and add (collect) them.

You should get a linear equation is x.

Then go back and compute all the angles.