Use the FOIL method (First, Outside, Inside, Last)
Reorder:
(2x + 5)(-4x + 7)
2x(-4x) = -8x²
2x(7) = 14x
5(-4x) = -20x
5(7) = 35
-8x² + 14x - 20x + 35
Combine like terms
-8x² (+ 14x - 20x) + 35
-8x² - 6x + 35
-8x² - 6x + 35 is your answer
hope this helps