1MA0 Higher June 2017 Paper 2 Q21
21 Solve \(2x^2 + 3x - 7 = 0\)
Give your solutions correct to 2 decimal places. (3)
| Working | Answer | Mark | Notes |
|---|---|---|---|
| \(\dfrac{-3 \pm \sqrt{3^2 - 4 \times 2 \times -7}}{2 \times 2}\) | 1.27, \(-2.77\) | 3 | M1 for substitution of \(a = 2\), \(b = 3\), \(c = -7\) (condone one sign error) M1 for \(\dfrac{-3 \pm \sqrt{65}}{4}\) A1 for solutions in range 1.26 to 1.27 and \(-2.76\) to \(-2.77\) |