Answer:
see explanation
Step-by-step explanation:
The sum of the interior angles of a quadrilateral = 360°
sum the 4 angles and equate to 360
y + 3y + y + 30 + 90 = 360 , that is
5y + 120 = 360 ( subtract 120 from both sides )
5y = 240 ( divide both sides by 5 )
y = 48
3y = 3 × 48 = 144
y + 30 = 48 + 30 = 78
The measure of the 4 angles are
48°, 78° , 90° , 144°
