To get the b of the standard form 15x²+_x-8, the factor is given. Use FOIL method or First, Outside, Inside, Last. So here's how to used or how I apply the FOIL method to get the b.First, multiply 5x and 3x to get the 15x².Outside, multiply 5x and 4 to get 20x.Inside, multiply -2 and 3x to get -6x.Last, multiply -2 and 4 to get -8[tex]____________________________[/tex]OR if that's not the answer maybe this...x=14 and x=0 (no explanation kasi mahirap po hope you understand)[tex]____________________________[/tex][tex]eya \gamma [/tex]