Mathematics · Oct / Nov 2024 · Paper 42 · Question 3

–m + 3n final answer [2]

B1 for –m or [+] 3n in final answer or for –m + 3n seen and then spoiled

8 12 81a c final answer [2]

B1 for final answer in correct form with any two of 81, a8, c12 correct or for 81a c seen and then spoiled 8 12

19 x final answer 30 [1]

× −× + × 2

M1 for 6 4 x 3 3 x 2 2 x oe 30

4.5 oe [3]

M1 for a + 2(3a + 2) = 35.5 oe

M1 for correct ka = b for their linear equation

−− ± − 2 −××− ( 4) ( 4) 4 5 ( 3) oe × 2 5 –0.472 or –0.4718 to –0.4717 and 1.27 or 1.271 to 1.272 [4]

M2 M1 for − −××− ( 4) 2 4 5 ( 3) or better −− + −− − ( 4) q ( 4) q or for or or better × × 2 5 2 5 B1

x2 – 6x + 8 [= 0] or y2 – 6y + 5 [= 0] (x – 4)(x – 2) [= 0] or (y – 1)(y – 5) [=0] OR −− ± − 2 − × × ( 6) ( 6) 4[ 1] 8 [x = ] × 2[ 1] or −− ( 6) ± ( 6) − 2 − 4[ 1] 5 × × [y = ] × 2[ 1] OR ± −+ [x = ] 3 8 9 or ± −+ [y = ] 3 5 9 [x = ] 2 , [y = ] 1 [x = ] 4 , [y = ] 5 [7]

M2 M1 for x2 – 4x + 5 = 2x – 3 or 2 y + 3 y + 3 − + y = 4 5 2 2 M1 FT their 3-term quadratic but not if x2 – 4x + 5[= 0]

B2 B1 for one correct pair or two correct x-values or two correct y-values If B0 scored and at least 2 method marks scored,

SC1 for correct substitution of both of their x values or their y values into y = x2 – 4x + 5 or y = 2x – 3