Foundation June 2019 Paper 1 Q12
12 \(AB\) and \(BC\) are perpendicular lines.
(a) Find the value of \(x\). (2)
\(RS\) and \(TU\) are parallel lines.
\(PQ\) is a straight line.
An angle of size 125° is shown on the diagram.
(b)
(i) Write down the letter of one other angle of size 125°
Give a reason for your answer. (2)
Give a reason for your answer. (2)
(ii) Explain why \(a + b + c = 235^\circ\) (1)
| Answer | Mark | Mark scheme |
|---|---|---|
| 40 | M1 | for using 90, eg \(90 - 25 - 25\) |
| A1 | cao |
Additional guidance
\(90 - 25\) is enough for this mark
| Answer | Mark | Mark scheme |
|---|---|---|
| b or d with reason | B1 | for \(b\) or \(d\) (or both) |
| C1 | (dep) for appropriate reason(s) vertically opposite angles are equal vertically opposite angles are equal corresponding angles are equal alternate angles are equal angles on a straight line add up to 180 |
Additional guidance
For the B1: A correct answer can be implied by writing 125 immediately next to \(b\) or \(d\) (or both) as long as 125 is not written next to an incorrect angle.
For the C1: Underlined words need to be shown; reasons need to be linked to their method; any reasons not linked, do not credit. There should be no incorrect reasons given.
| Answer | Mark | Mark scheme |
|---|---|---|
| reason | C1 | for correct explanation using 360 or a full explanation using angles around a point Acceptable examples Because 360 around a point \(360 - 125 = 235\) \(125 + 235 = 360\) Because they add to 360 Not acceptable examples Because b is 125 |
Additional guidance
Using 360 appropriately and not in an incorrect setting