Hope this helps! The way I did it was you multiply the first and third number and then just left b. Then I find a number that multiplies to what you got for a x c (ex. A=4 c=1 4x1 = 4 and a multiple is 2x2 and 4x1) and a set of numbers that adds to b (ex. B= 4 so 2+2= 4 and 3+1= 4, but because the numbers have to both multiple and add, the best option is 2 and 2) if that makes sense. I demonstrate this in the picture I provided below
