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Find all solutions to the equation $x^2 - 7x = 30$. If you find more than one, then list the values separated by commas. If the solutions are not real, then they should be written in $a + bi$ form.

Respuesta :

bluegreen24

Answer: {10, -3}

Step-by-step explanation:

  • [tex]0 =x^{2} - 7x - 30[/tex]
  • [tex]0 = (x - 10)(x+3)[/tex]
  • [tex]0 = x - 10[/tex]
  • [tex]10 = x[/tex]
  • [tex]0 = x+3[/tex]
  • [tex]-3 = x[/tex]

Check:

  • [tex](10)^{2} - 7(10) = 30[/tex]
  • [tex]100 - 70 = 30[/tex]
  • [tex]30 = 30[/tex]
  • [tex](-3)^{2} - 7 (-3) = 30[/tex]
  • [tex]9- (-21) = 30[/tex]
  • [tex]30 = 30[/tex]
MindTrickery

Answer:-3, 10

Step-by-step explanation:

Subtracting 30 from both sides gives x^2 - 7x - 30 = 0. The quadratic factors as

(x - 10)(x + 3) = 0, so the solutions are x = 10 and x = -3.

Instead of factoring, we also could have applied the quadratic formula with a = 1, b = -7, and c = -30:

Ver imagen MindTrickery

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