if and are two roots of a quadratic ...
now, substitute and to determine the basic quadratic in [...], then use the fact that to find
There are several approaches to this problem.
. . Here's one of them . . .
Find the equation of the quadratic given its real roots and
which passes through the point (1,-2)
If the quadratic, , has roots , then: .
So we have: . .
. . The function (so far) is: .
Since (1,-2) is on the graph: .
. . Hence: .