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 The sum of the measures of the angles of a quadrilateral is 360º. x+y+z+w=360º Find the value of x in the quadrilateral Since the sum of the angle measures in a quadrilateral is 360º, x+65+85+90=360

 x + 65 + 85 + 90 = 360 Write the equation x + 240 = 360 Add 65, 85, and 90 x+240-240 = 360-240 Subtract 240 from each side x = 120 Simplify

So, the value of x is 120º.

 Find the value of x in the quadrilateral Since the sum of the angle measures in a quadrilateral is 360º, x+106+131+67=360

 x + 106 + 131 + 67 = 360 Write the equation x + 304 = 360 Add 106, 131, and 67 x+304-304 = 360-304 Subtract 304 from each side x = 56 Simplify

So, the value of x is 56º.