Pls help, I’m quite confused.
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Answer:
A
Step-by-step explanation:
[tex] {x}^{2} + 4x = 15[/tex]
[tex] {x}^{2} + 4x + 4 = 15 + 4[/tex]
[tex](x + 2) {}^{2} = 19[/tex]
[tex]x + 2 = \sqrt{19} [/tex]
[tex]x = \sqrt{19} - 2[/tex]
[tex]x = - 2 - \sqrt{19} [/tex]