p(x) = 2x² - 3x + 1 and r(x) = x² - 5x

r(x) - p(x + 1)

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

x² - 5x - [2(x + 1)² - 3(x + 1) + 1]

x² - 5x - [2(x² + 2x + 1) - 3x - 3 + 1]

x² - 5x - [2x² + 4x + 2 - 3x - 2]

x² - 5x - [2x² + x]

x² - 5x - 2x² - x

-x² - 6x