From the sum of 4 + 3x and 5 - 4x + 2x2, subtract the sum of 3x2 – 5x and -x2 + 5.
The equation for the problem is
[(4 + 3x) + (5 - 4x + 2x2 ) -[ ( 3x2 - 5x) + ( -x2 + 2x +5)]
=[ 4 + 3x + 5 - 4x + 2x2 ] - [3x2 - 5x - x2 + 2x + 5]
=4 + 3x + 5 - 4x + 2x2 - 3x2 + 5x + x2 - 2x - 5
=2x2 - 3x2 + x2 + 3x - 4x + 5x - 2x + 4 + 5 - 5
=2x + 4