Intermediate June 2017 Unit 1 Q17
17. Solve the following simultaneous equations using an algebraic (not graphical) method. [4]
\[\begin{aligned} 3x + 4y &= 7 \\ 2x - 3y &= 16 \end{aligned}\]| Scheme | Marks | Comments |
|---|---|---|
| No marks for ‘trial and improvement’. | ||
| Method to eliminate variable e.g. equal coefficients with intention to appropriately add or subtract’ | M1 | Allow 1 error in one term, not one with equal coefficients. |
| First variable found x = 5 or y = −2. | A1 | C.A.O. |
| Substitute to find the 2nd variable. | m1 | F.T. their ‘1st variable’. |
| Second variable found. | A1 |