Question

$(x + 5)(7 - x) (x - 1)then(3x + 7)(x - 10) \times 5$

Answer 1

[(x+5)(7-x)](x-1) =(35+2x-x^2)(x-1)
                          = 33x-x^3+3x^2 -35

(3x+7)(x-10) x5 = ( 3x^2 - 3x-70 )x5
                          = 15x^2 - 15x -350