You wrote (4x^2 -2x 3) - (-3x^2 2x -5)
There's a + or - missing in front of the 3 and the 2x.
If you meant (4x^2 -2x +3) - (-3x^2 +2x -5) then
first, distribute the - sign into the parentheses on the right
4x^2 -2x +3 +3x^2 -2x +5
combine the x^2 parts
7x^2 -2x +3 -2x +5
combine the x parts
7x^2 -4x +3 +5
combine the numbers without an x
7x^2 -4x +8
If you meant (4x^2 -2x +3) - (-3x^2 -2x -5) then
7x^2 +8
If you meant (4x^2 -2x -3) - (-3x^2 +2x -5) then
7x^2 -4x +2
If you meant (4x^2 -2x -3) - (-3x^2 -2x -5) then
7x^2 +2