Ax2+Bx+C

Box 1:  Put A

Box 2:  Put C

Box 3:  Multiply A x C

Box 10:  Put B

Boxes 4 & 7:  Put an x in each box

Boxes 6 & 9:  Find two factors that multiply to give you the value of box 3                          and add to give you the value of box 10.

Boxes 4 & 5:  Find two factors of box 6.  The factor you place in box 4                              should divide evenly into box 1.  The factor you place in box                             5 should divide evenly into box 2.

Boxes 7 & 8: Find two factors of box 9.  The factor you place in box 7                               should divide evenly into box 1.  The factor you place in box                            8 should divide evenly into box 2.