Question 1: Calculate the missing angle on a straight line if one adjacent angle is 65°.

Answer: 115

Question 2: A straight line forms two angles: 120° and x°. Find x.

Answer: 60

Question 3: If an angle on a straight line is 85°, what is the other angle?

Answer: 95

Question 4: Construct a straight line with an angle of 40°. Calculate the other angle on the same line.

Answer: 140

Question 5: Identify and correct the mistake: A student says that if one angle on a straight line is 70°, the other should be 70° as well.

Answer: The other angle should be 110°, as angles on a straight line sum to 180°.

Question 6: A straight line has an angle of 150° adjacent to an unknown angle x°. Find x.

Answer: 30

Question 7: A diagram shows a straight line with angles 50° and x° on either side of a point. If the angles are supplementary, find x.

Answer: 130

Question 8: In a straight line, two angles are 110° and y°. A student claims y = 110°. Explain whether this is correct and justify your answer.

Answer: Incorrect; y = 70°, since angles on a straight line sum to 180°.

Question 9: Plot the graph of y = 2x on the provided grid. Describe the slope of the line.

Answer: The slope is 2.

Question 10: A student makes the error of subtracting angles instead of adding when calculating a missing angle on a straight line. Identify and correct this error with an example.

Answer: Correct approach: angles on a straight line sum to 180°. Example: if one angle is 45°, the other is 135°, not 45° minus 180°.

Question 11: A diagram shows two angles 60° and 90° adjacent on a straight line, with an unknown angle x. Find x and explain the common misconception involved.

Answer: x = 30°, misconception: adding the angles instead of subtracting from 180°.