[tex](5x - 7) * (9x^2 - 4x - 8)[/tex]
1.) Try using the FOIL method (First*first, outside*outside, inside*inside, last*last):
[tex](5x)(9x^2) + (5x)(-4x) + (5x)(-8) + (-7)(9x^2)[/tex]
2.) Multiply the bases and add the exponents:
[tex]45x^3 - 20x^2 - 40x - 63^2 + 28x + 56[/tex]
3.) Look for the variables without exponents:
[tex]-40x + 28x[/tex] = 28x
[tex]45^3 - 83x^2 - 12x + 56[/tex]
