5% of £42 = £2.10
10% of £42 = £4.20
15% of £42 = £6.30
£42 - £6.30 = £35.70
£50 - £35.70 = £14.30
the answer is £14.30
X⁴ + x³ - 2x² + x + (2x⁴ - 2x²<span> - 3) =
</span>x⁴ + x³ - 2x² + x + 2x⁴ - 2x² - 3 =
3x⁴ + x³ - 4x² + x - 3 ← <span>the missing polynomial</span>