Aider moi svp au plus vite merci d'avance

a) (2x+5) (x+1) ?? 
=2x²+2x+5x+5
=2x²+7x+5
b) (2y-1) (3y+2) ??
=6y²+4y-3y-2
=6y²+y-2
c) (x+7) (3x-1) ??
=3x²-x+21x-7
=3x²+20x-7
d) (2t-3) (2t-1) ??
=4t²-2t-6t+3
=4t²-8t+3