Quadratics and Cubics, SMB-034 Solve the equation `21-4b^2=5b` for `b.` (2 marks) --- 4 WORK AREA LINES (style=lined) --- Show Answers Only `b=7/4 \ text{or}\ -3` Show Worked Solution `21-4b^2` `=5b` `4b^2+5b-21` `=0` `(4b-7)(b+3)` `=0` `4b-7` `=0` `text{or}\ \ \ \ b=-3` `b` `=7/4`