n - a number
14. Nine more than the square of a number: n² + 9.
15. Twice the difference between a number and ten: 2(n - 10)
(2x²<span> + 3x - 4) + (8 - 3x) + (-5x</span>²<span> + 2)
= </span> 2x² + 3x - 4 + 8 - 3x - 5x² + 2
= -3x² + 6
= 3(-x² + 2)
Opening brackets gives;
4-8v=-8v+4
Putting like terms together;
4-4=-8v+8v
0=0
There is no solution thus.