(6x-1)(x+14)=160 because b is 20 and total they equal 180 so you -14 from both sides then you have 6x-1+x=146 then you add 1 to both sides and you have 7x=147 then you divide 7 from both sides and get 21=x and then you (6(21)-1) =125 =A
((21)+14) =35 =C
hope that helps
