Angles at points, lines and parallel lines
3 exam-style questions. Answers and the mark for each step are on the last page.
- Question 1
(a) Three adjacent angles on one side of a straight line are , and Work out x.
- Question 2
Two co-interior angles between parallel lines are and .
(a) Find x.
(b) Find the smaller angle.
- Question 3
A straight line crosses the lines and at and . At the angles on one side of are and , and they lie on the straight line . At , the angle corresponding to the angle is .
(a) Is parallel to ? You must show how you get your answer.
Answers and marks
Question 1
(a) °
- P1 Establishing or an equivalent valid method.
- A1 Correct answer: °
Question 2
(a)
- M1 Co-interior angles between parallel lines are supplementary.
- A1 Correct answer:
(b) °
- M1 Substitute into the smaller angle expression.
- A1 Correct answer: °
Question 3
(a) No: , so the corresponding angles are and , which are not equal.
- P1 Forming the equation from angles on a straight line.
- P1 Solving to .
- P1 Working out both corresponding angles, and .
- C1 "Not parallel", because the corresponding angles ( and ) are not equal.