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Angle Reasoning: Triangles and Parallel Lines — Mixed

Find each missing angle and say which angle fact you used.

ExampleTwo parallel lines are cut by a transversal. One angle is 68°. Find x. → x = 68°, because corresponding angles on parallel lines are equal.
  1. 1.PQR37°79°x
    Find x, and give the reason.
    x =
    Reason:
  2. 2.52°x
    The two horizontal lines are parallel. Find x, and give the reason.
    x =
    Reason:
  3. 3.48°73°PQRy
    Side PQ is extended past Q. Find the exterior angle y, and explain why it equals the sum of the two angles at P and R.
    y =
    Why?
  4. 4.PQR46°75°59°
    Triangle XYZ has angles of 46° and 75°. Is triangle XYZ similar to triangle PQR? State what the third angle of XYZ must be.
    yesno   third angle
    Why?
  5. 5.PQR48°60°x
    Find x, and give the reason.
    x =
    Reason: