Answer:
-3x^4 - 13x^3 + 14x - 7
Step-by-step explanation:
(5x^4 – 9x^3 + 7x – 1) + (-8x^4 + 4x^2 – 3x + 2) - (-4x^3 + 5x - 1)(2x – 7)
simplify multiplied terms
(-4x^3 + 5x - 1)(2x – 7)
(-4x^3+10x-8)
group like terms together
(5x^4-8x^4) + (-9x^3-4x^3) + (7x-3x+10x) + (-1+2-8)
simplify grouped terms
-3x^4 - 13x^3 + 14x - 7
