Question 1: Calculate the missing interior angle of a quadrilateral if three angles are 80°, 100°, and 90°.

Answer: 90

Question 2: Two angles of a quadrilateral are 110° and 85°. Find the third angle if the sum is 360°.

Answer: 165

Question 3: A quadrilateral has one right angle and the others are 95°, 85°, and an unknown angle. Find the unknown angle.

Answer: 95

Question 4: Construct a quadrilateral where three angles are 70°, 85°, and 100°. Use the grid to draw it and label the missing angle.

Answer: 105

Question 5: Plot the graph of y=2x on the grid and identify the coordinates where the line intersects the x-axis and y-axis.

Answer: x-intercept: 0, y-intercept: 0

Question 6: A regular quadrilateral has all angles equal. What is each interior angle?

Answer: 90

Question 7: In a quadrilateral, three angles are 120°, 50°, and x°. Find x.

Answer: 190

Question 8: A quadrilateral has angles measuring 85°, 95°, and 100°. Calculate the fourth angle.

Answer: 80

Question 9: A student mistakenly adds the angles as 90°, 90°, 90°, and 90° for a quadrilateral. Identify the mistake and explain why the sum is incorrect.

Answer: The sum of the angles in a quadrilateral is always 360°, so adding four 90° angles giving 360° is correct; the mistake is assuming they are all right angles without verifying.

Question 10: A rectangular park has one corner with an interior angle of 90°. If one adjacent side extends 50 meters and the other 80 meters, find the total sum of the angles in the surrounding quadrilateral if it extends further.

Answer: The sum of angles remains 360°; the problem involves understanding that the shape remains a quadrilateral.

Question 11: Identify the common mistake in calculating the missing angle if someone incorrectly uses 370° instead of 360° as the total sum.

Answer: The mistake is adding an extra degree; the correct total for the sum of interior angles in a quadrilateral is 360°, not 370°.

Question 12: Challenge: A quadrilateral has three known angles: 75°, 85°, and 95°. The fourth angle is twice the measure of the second angle. Find all four angles.

Answer: Second angle = 85°, fourth angle = 2 × 85 = 170°, sum = 75 + 85 + 95 + 170 = 425°. Since total should be 360°, there is no quadrilateral with these angles; the problem demonstrates the importance of valid angle combinations.