You can 
put this solution on YOUR website!   
Hi
multiplying
(5x+6)(8x^2+7x+1)   |Assuming the 8x^2
Multiplication is accomplish in 2 steps:
1) 5x(8x^2+7x+1) + 6(8x^2+7x+1)  |Completing these multiplications
   40x^3+35x^2+5x + 48x^2 +42x+6
2) combining Like terms
  40x^2 + 83x^2 + 47x  + 6
Always recommend rechecking for any arithmetic errors that may have occurred.