Foundation November 2020 Paper 2 Q21
21
(a) Simplify \(\;g^6 \times g^4\) (1)
(b) Simplify \(\;(3cd^4)^2\) (2)
(c) Solve the simultaneous equations
\(\begin{aligned} 4x + 3y &= 17 \\ x + 2y &= 5 \end{aligned}\)
Show clear algebraic working. (3)
\(\begin{aligned} 4x + 3y &= 17 \\ x + 2y &= 5 \end{aligned}\)
Show clear algebraic working. (3)
| Scheme | Marks |
|---|---|
| \(g^{10}\) | B1 |
| (1) |
| Scheme | Marks |
|---|---|
| \(9c^2d^8\) | B2 |
| (2) |
Notes
B2: B1 for 2 out of 3 terms correct as part of a product
| Scheme | Marks |
|---|---|
| eg \(4x + 3y = 17\) \(-\;\;4x + 8y = 20\) or eg \(4(5 - 2y) + 3y = 17\) or eg \(8x + 6y = 34\) \(-\;\;3x + 6y = 15\) or eg \(4x + 3 \times \tfrac{1}{2}(5 - x) = 17\) | M1 |
| eg \(4x + 3 \times 0.6 = 17\) or \(x + 2 \times 0.6 = 5\) or eg \(4 \times 3.8 + 3y = 17\) or \(3.8 + 2y = 5\) | M1 |
| Working required Answer: \(x = 3.8\) \(y = 0.6\) | A1 |
| (3) | |
| (6 marks) |
Notes
M1: Correct method to eliminate \(x\) or \(y\): coefficients of \(x\) or \(y\) the same and correct operation to eliminate selected variable (condone any one arithmetic error in multiplication) or writing \(x\) or \(y\) in terms of the other variable and correctly substituting
M1: (dep) correct method to find second variable – could start process again or use substitution
A1: oe for both solutions dep on first M1