3 a M1 2 M1 for correctly expanding the brackets B 5(c + 4) = 5c + 20 C1 C1 for suitable feedback to multiply out both Feedback: Don’t forget terms in the brackets. M1 M1 for correctly expanding the brackets b 6(t 2) = 6t 12 – – C1 C1 for suitable feedback means Feedback: Don’t forget 6(…..) multiply both terms by 6. c M1 M1 for correctly expanding the brackets s) = + 3s –3(4 – –12 C1 C1 for suitable feedback means Feedback: Don’t forget –3(……) M1 M1 for correctly expanding the brackets multiply both terms by 6 and minus × minus = … d n n 15 (n 4) = 15 + 4 = 15 + 4 – – – – n C1 C1 for suitable feedback = 19 – 4) means Feedback: Don’t forget –(n – multiply each term inside the brackets by –1 and that the inside the brackets belongs to 8 – the 4 to make it 4. – 4 Start with numbers that work. M1 2 M1 for first method, e.g. starting with numbers B = 2.5 3 z So = will satisfy conditions. Start with a formula. e.g. A1 A1 for an example that works z = z s t x. Substitute = 2.5, = 6, = 2 to find M1 for second method, e.g. starting with a formula M1 x 5 = 18 8 + – x = –5 z so = satisfies conditions. B1 B1 for an example that works C1 C1 for a clear, complete solution showing two different methods and two examples 5 5 M1 2 M1 for factorising B = B1 B1 for any correct expression n = + 3 2
3 a b c d 5(c + 4) = 5c + 20 Feedback: Don’t forget to multiply out both terms in the brackets. 6(t – 2) = 6t – 12 Feedback: Don’t forget 6(…..) means multiply both terms by 6. –3(4 – s) = –12 + 3s Feedback: Don’t forget –3(……) means multiply both terms by 6 and minus × minus = … 15 – (n – 4) = 15 – n + 4 = 15 + 4 – n = 19 – n Feedback: Don’t forget –(n – 4) means multiply each term inside the brackets by –1 and that the – inside the brackets belongs to the 4 to make it – 4. M1 C1 M1 C1 M1 C1 M1 C1 2 M1 for correctly expanding the brackets C1 for suitable feedback M1 for correctly expanding the brackets C1 for suitable feedback M1 for correctly expanding the brackets C1 for suitable feedback M1 for correctly expanding the brackets C1 for suitable feedback B 8 4 Start with numbers that work. = 2.5 So z = will satisfy conditions. Start with a formula. e.g. z = Substitute z = 2.5, s = 6, t = 2 to find x. 5 = 18 – 8 + x x = –5 so z = satisfies conditions. M1 A1 M1 B1 C1 2 3 M1 for first method, e.g. starting with numbers A1 for an example that works M1 for second method, e.g. starting with a formula B1 for an example that works C1 for a clear, complete solution showing two different methods and two examples B 5 5 = = n + 3 M1 B1 2 M1 for factorising B1 for any correct expression B 2
Higher_Skills_Algebra_MarkScheme_Edexcel.docx