Find the roots of the equation, and check them using the Vieta's theorem: x^2−15x−16=0

The roots are fairly simple to find, no need to invoke quadratic formula. First we factor,

Then we get zeros at .

Using veita's formulas we can check it namely,

So as you can see solutions pass both tests and therefore are valid.

Hope this helps.

12*c

step-by-step explanation:

-362

step-by-step explanation:

(12)(4)+2(12)-34(12)+2(12)-3

  \/         \/         \/         \/

  48 +   24 -   408 + 24 - 3

      \   /               \   /

          72     -     432 - 3 = -363