Solve the simultaneous equations. You must show all your working. 2a + 5b = 1.5 3a - 10b = 42.5

Mark scheme

Marking points from the official mark scheme (Oct/Nov 2025). The mark or mark type is shown in brackets.

1. 13 Correct method to eliminate one variable M1 E.g. substitution of a = (1.5-5b)/2 or b = (1.5-2a)/5 or equating coefficients.
2. 13 [a = ] 6.5 oe [b = ] -2.3 oe nfww A2 A1 for either a = 6.5 oe or b = -2.3 oe nfww or if A0 scored, SC1 for a pair of values that satisfy either equation or for correct answers with no working