How do you factor and solve 6b^2 - 13b + 3 = -3?

1 Answer

Rewrite 6b^2 - 13b + 3 = -3
as
6b^2-13b+6=0

Assuming only integer values appear in the factoring (not necessarily true, but easier if it is)
we are looking for integer values for p, q, r, and s (all >= 0)
such that
(pb-q)(rb-s) = 6b^2-13b+6
(the negative sign on the coefficient -13 tells us that at least one of the internal signs in the factors is negative, assuming positive values for p, q, r, s
and the positive sign on +6 tells us that the internal signs are the same i.e. they are both negative).

(pb-q)(rb-s) = (pbr)b^2 - (ps+qr)b + qs
rarr pb = 6
rarr ps+qr = 13
rarr qs = 6

Since the only positive integer factors of 6 are 6xx1 and 3xx2

It is a fairly simply matter to discover
p=3
q=2
r=3
s=2

That is
(3b-2)^2 = 6b^2-12b+6 = 0

Which implies there is only one solution (3b-2=0)
b=2/3