2x is squared and the x is squared in x-5x and (x)

p(x) = 2x^{2} - 3x + 1 and r(x) = x^{2} - 5x

r(x) - p(x + 1)

Remember that you are replacing each x in p(x) with an x + 1

x^{2} - 5x - [2(x + 1)^{2} - 3(x + 1) + 1]

x^{2} - 5x - [2(x^{2} + 2x + 1) - 3x - 3 + 1]

x^{2} - 5x - [2x^{2} + 4x + 2 - 3x - 2]

x^{2} - 5x - [2x^{2} + x]

x^{2} - 5x - 2x^{2} - x

-x^{2} - 6x