Quadratic equation

Determine the numbers b, c that the numbers x₁ = -1 and x₂ = 3 were roots of quadratic equation:

$-3x^2+bx+c=0$

Correct answer:

b =  6
c =  9

Step-by-step explanation:

$$\begin{gathered} a=-3 \\ b=-a{x}_1-a{x}_2=6 \end{gathered}$$

$$\begin{gathered} c=a{x}_1{x}_2=9 \\ -3x^2+6x+9=0 \end{gathered}$$

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