Question 678341
Find the value of b so that the equation will have exactly one rational solution.  

12p^2+bp+3=0
----------------
2nd order equations ALWAYS have 2 solutions.
Sometimes it's the same solution, multiplicity 2, but there are 2 solutions.
---------------
To have the same solution twice, the discriminant = 0
{{{b^2 - 4ac = 0}}}
{{{b^2 - 4*12*3 = 0}}}
{{{b^2 = 144}}}
b = -12
b = +12