The answer is 1680. To get this you do 8*7*6*5 because there are 8 options for the first character, and then you can repeat that for the second one with 7, 6, and 5
You can factor (x^3 and 6x^2) and (-4x and -24).
So x^2(x+6) - 4(x+6)
(x^2-4)(x+6)
(x-2)(x+2)(x+6)
So what we do is
area that remains=total area-triangle area that was cut out
we need to find 2 things
total area
triangle area
total area=rectange=base times height
area=(3x+4) times (2x+3)
FOIL or distribute
6x^2+8x+9x+12=6x^2+17x+12
triangle area=1/2 times base times height
triangle area=1/2 times (2x+2) times (x-2)=
(x+2) times (x-2)=x^2+2x-2x-4=x^2-4
so
total area=6x^2+17x+12
triangle area=x^2-4
subtract
area that remains=total area-triangle area that was cut out
area that remains=6x^2+17x+12-(x^2-4)=
6x^2+17x+12-x^2+4=
6x^2-x^2+17x+12+4=
5x^2+17x+16
area that remains is 5x^2+17x+16
