Question 1: Calculate the missing angle if one angle on a straight line is 120°.

Answer: 60

Question 2: On a straight line, two angles are 70° and x°. Find x.

Answer: 110

Question 3: Construct a straight line with angles 130° and y°. Calculate y.

Answer: 50

Question 1: Two angles on a straight line are 45° and an unknown angle z°. A third angle adjacent to the 45° is 125°. Explain why the angle adjacent to the 125° angle is not necessarily 180°.

Answer: Because the angles may not be on the same straight line; the diagram context is needed to determine if they are supplementary.

Question 2: A straight line has angles of 90°, 45°, and x°. Find x, and justify your answer.

Answer: 45

Question 1: A carpenter cuts a piece of wood with an angle of 135°. What is the supplementary angle needed to make a straight line?

Answer: 45

Question 2: In a city park, two fences meet at a straight boundary forming a 160° angle. What is the measure of the other angle where they meet?

Answer: 20

Question 1: Construct a diagram of a straight line with angles 110° and x°, where x° equals the supplement of 110°. Confirm your answer with calculation.

Answer: 70

Question 2: A straight line is divided into two angles: one is 65°, and the other is y°. If y° is mistakenly taken as 115°, identify and explain the misconception.

Answer: The misconception is assuming the two angles are supplementary when their sum exceeds 180°; angles on a straight line must sum to exactly 180°.

Question 1: A student states that two angles measuring 90° and 95° on a straight line are both valid. Explain the error and the correct understanding.

Answer: Angles on a straight line must add to 180°, so 95° is incorrect in this context.

Question 2: A diagram shows an angle of 180° with an incorrect label of 170°. Identify the mistake and correct it.

Answer: The angle on a straight line must be 180°, so the label should be corrected to 180°.