B1 for 110

(ii) Angles around a point total 360°

B1 for a correct full reason

[2]

2. (a) 132 1 180 − 48

B1 for 132

(b) (i) 66 3 (180 − 48) ÷ 2

B1 for 66

(ii)

3rd angle in triangle = y° (isosceles triangle) y + y + 48 = 180 (angles in triangle sum to 180°)

B1 for isosceles triangle

B1 for either angles in triangle sum to 180° or exterior angle of triangle = sum of two interior opposite angles

[4]

3. 142 4 2x + x + 100 + 47 = 360

2x + x = 360 – 100 – 47 x = 71

Largest angle = 2x =

M1 for 2x + x + 100 + 47 = 360 or 360 – 147 or 213 seen

M1 dep for correctly separating x-terms and non x terms or “360 – 147” ¸ 3

A1 for x = 71provided M2 awarded

A1 ft for 142

[4]

4. (a) 135 3 Exterior angle = = 45

Int angle = 180 - 45

M1 for OR “6” ´ 180 oe

M1 for 180 - “45” OR

A1 cao

(b) 12 2 M1 for

A1 cao

[5]

5. (a) (i) 38 2

B1 for 38

(ii) alternate

B1 for alternate (or Z) angles

(b) 109 2 (180 – 38) ÷ 2 = 142 ÷ 2 = 71

M1 for (180 – “38”) ÷ 2 or 71 seen

A1 ft from (a)(i)

[4]

6. (a) (i) 60 2

B1 cao

(ii) eg top triangle is equilateral

B1 for reason

(b) 150 2

M1 for + 90

A1 ft from (a)(i) if x < 90

SC B1 for “60” + 90 if x < 90

[4]

7. (a) (i) 60 2

B1 for 60

(ii)

B1 for all angles equal so equilateral triangle oe

(b) (i) 130 3

B1 for 130

(ii)

B1 for isosceles triangle oe or 2 angles equal accept ÐQ = ÐR

B1 for angles on a straight line add up to 180°oe (180º could be in working)

(c) 64