Higher June 2023 Paper 2R Q20

EdexcelHigherCurrent spec2 marksCircle Theorems

20 \(A\), \(B\) and \(C\) are points on a circle.

Triangle ABC inscribed in a circle with AB and CB marked equal; MN is the tangent at C and angle BCN = 78 degrees

Diagram NOT accurately drawn

\(MN\) is the tangent to the circle at \(C\)

\(AB = CB\)

Angle \(BCN = 78^\circ\)

Find the size of angle \(ABC\)

(2)

Mark scheme

Scheme	Marks
180 – 78 – 78 oe or (90 – 78) × 2 oe	M1
Correct answer scores full marks (unless from obvious incorrect working) Answer: 24	A1
	(2)
	(2 marks)

Notes

M1: for a complete correct method to find angle \(ABC\). This is not awarded if the angles are incorrectly labelled unless they have clearly started again
(Ignore incorrect angles on the diagram if a student shows a correct method leading to the required answer)

A1: award full marks if 24 is seen in the correct place on the diagram unless contradicted on the answer line