Question 407134
Suppose that x and y are the numbers, such that x + y = 7 and xy = 11. Two ways to solve this:


Solution 1:
Substitute y = 7 - x into the second equation to obtain x(7 - x) = 11. Now you can find x using the quadratic formula.


Solution 2: Assume that x and y are roots of a polynomial of the form {{{z^2 + bz + c}}}. Applying Viete's formulas, the sum of the roots of the polynomial is -b, and the product is c, so we have


{{{z^2 - 7z + 11 = 0}}}. The roots of z are the values of x and y. Note that this is the same quadratic as in the previous solution.