By using the quadratic formula, and setting a=8, b=30, and c=7, you end up with:
[-30 +/- SqurRt( 30^2-4(8)(7) )/ 2(8)]
After simplifying that equation, you end up with (-30 +/- 26)/(16)
When solving for the equation where 26 is positive, the result for m is m= -0.25
When solving for when 26 is negative, the result is m= -3.5
since m^2 has a coefficient of 8, you would multiply m= -0.25 by 4 to get 4m= -1. Then you would multiply the other m by 2, to get 2m= -7
setting those two equations for m equal to zero would leave you with (4m+1)(2m+7).
This could have also been done without the quadratic formula if you guessed right on which coefficients for m to use
