A. Find the solutions of the following quadratic equations using the method specified on each item. (3 pts, each) x²-8x+12=0 3. x²-6x-7=0 (use factoring) (use completing the squarel

Respuesta :

For x²-8x+12=0, we have:

[tex]x^2-8x+12=0[/tex]

Factoring the expression:

[tex]\begin{gathered} \left(x^2-2x\right)+\left(-6x+12\right)=0 \\ x(x-2)-6(x-2)=0 \end{gathered}[/tex]

Factor the common term x - 2:

[tex](x-2)(x-6)=0[/tex]

Separate the solutions:

[tex]\begin{gathered} x-2=0 \\ x-2+2=0+2 \\ x=2 \\ and \\ x-6=0 \\ x-6+6=0+6 \\ x=6 \end{gathered}[/tex]

Answer: x = 2 and x = 6

For x²-6x-7=0, we have:

[tex]x^2-6x-7=0[/tex]

Factor the expression:

[tex]\begin{gathered} \left(x^2+x\right)+\left(-7x-7\right)=0 \\ x(x+1)-7(x+1)=0 \end{gathered}[/tex]

Factor x + 1:

[tex](x+1)(x-7)=0[/tex]

The solutions are:

[tex]\begin{gathered} x+1=0 \\ x+1-1=0-1 \\ x=-1 \\ and \\ x-7=0 \\ x-7+7=0+7 \\ x=7 \end{gathered}[/tex]

Answer: x = -1 and x = 7