Higher November 2017 Unit 1 Q9
9. Solve the following simultaneous equations using an algebraic (not graphical) method. [4]
\[\begin{aligned} 4x - 3y &= 2 \\ 6x - 5y &= 1 \end{aligned}\]| Scheme | Marks | Comments |
|---|---|---|
| Method to eliminate variable e.g. equal coefficients with appropriate addition or subtraction. | M1 | No marks for trial and improvement. Allow 1 error in one term, not one with equal coefficients. |
| First variable found, \(x = 3\tfrac{1}{2}\) or \(y = 4\). | A1 | C.A.O. |
| Substitute to find the 2nd variable. | m1 | F.T. their ‘1st variable’. |
| Second variable found | A1 |