Moderate -0.5 This is a straightforward algebraic manipulation requiring expansion, collection of terms with y, and factorization. It's slightly easier than average because it follows a standard procedure (expand, collect like terms, factor) with no conceptual difficulty, though it requires careful execution of multiple steps for 4 marks.
Question 13:
13 | y + 5 = xy + 2x
y − xy = 2x − 5 oe or ft
y (1 − x) = 2x − 5 oe or ft
2x−5
[y =] oe or ft as final answer
1−x | M1
M1
M1
M1 | for expansion
for collecting terms
for taking out y factor; dep on xy term
for division and no wrong work after
ft earlier errors for equivalent steps if
error does not simplify problem | 4