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Inga is solving 2x2 + 12x – 3 = 0. Which steps could she use to solve the quadratic equation? Select three options.

2(x2 + 6x + 9) = 3 + 18
2(x2 + 6x) = –3
2(x2 + 6x) = 3
x + 3 = Plus or minus StartRoot StartFraction 21 Over 2 EndFraction EndRoot
2(x2 + 6x + 9) = –3 + 9

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facundo3141592

To complete squares, she must use, in order:

  • Third step.
  • First step.
  • Fourth step.

Which steps could she use to solve the quadratic equation?

Here we have the quadratic equation:

[tex]2x^2 + 12x - 3 = 0\\[/tex]

There are some ways of solving this, the first approach is completing squares, where we can write:

[tex]2(x^2 + 6x) - 3 = 0\\\\2(x^2 + 2*3*x + 9 - 9) -3 = 0\\[/tex]

Here we add and subtract 9 to complete squares and not change the equation. Here we used the third step only.

Now we just complete squares to get:

[tex]2*(x^2 + 6x + 9) - 2*9 - 3 = 0\\\\2(x^2 + 6x + 9) = 3 + 18 = 21\\\\2*(x + 3)^2 = 21\\\\x + 3 = \pm \sqrt{\frac{21}{2} }[/tex]

Where the first and fourth steps are also used.

If you want to learn more about quadratic equations:

https://brainly.com/question/1214333

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