posted by Ann on .
How do I solve this equation? Please explain and do step by step.
6m squared -5m-14=0
6m^2 - 5m - 14 = 0
it's mainly trial and error. Since 5 is a relatively small number, don't expect to see factors like (6m+1)(m-14)
I'd try (3m-?)(2m+?)
(3m-)(2m+) Hmm. nope
(6m-7)(m+2) = 6m^2 + 5m - 14
close, but we need -5m. So,
Then you have to set each factor equal to zero and solve for m.
I actually have another way to factor instead of trial and erro.
you multiply the 6 times -14 to get -84
Then you think of a two numbers that multiply to =-84 and add up to be -5
They are -12 plus 7
rewrite as 6m^2 -12m + 7m -14
group (6m^2 -12m) + (7m -14)
take out common factors
6m(m -2) + 7 (m-2)
factor out the m-2
and you have (6m+7)(m-2)
It is a newer methos and eliminates the guessing. It works every time.
how do I solve (16)^3 +48(16)^2