Mariah started to find the solutions of x2 + 4x + 1 = 0. Her work is shown below. x2 + 4x + 1 = 0 x2 + 4x = –1 x2 + 4x + 4 = –1 + 4 (x + 2)2 = 3 Which describes the solutions of the equation?

since -2 and 3 are both rational, the sum and difference are both rational
since -2 and /3 are both rational, the sum and difference are both rational
since -2 is rational and /3 is irrational, the sum and difference are irrational.
Since /2 is rational and /3 is irrational, the sum and difference are irrational.

Respuesta :

Answer:

Since -2 is rational and √3 is irrational, the sum and difference are irrational.

Step-by-step explanation:

Given equation,

[tex]x^2 + 4x + 1 =0[/tex]

[tex]x^2 + 4x = -1[/tex]

[tex]x^2 + 4x + 4 = -1+4[/tex]

[tex](x+2)^2 = 3[/tex]

[tex]x+2=\pm \sqrt{3}[/tex]

[tex]x=-2\pm \sqrt{3}[/tex]

Which is the solution of given equation.

Now, an integer is always a rational number ( that can be expressed as  [tex]\frac{p}{q}[/tex], where, p and q are integers such that q ≠ 0 ),

So, -2 is a rational number,

Now, √3 can not be expressed as p/q so it is an irrational number,

We know that sum and difference of rational and irrational number is always irrational.

Thus, -2 + √3 and -2 - √3 are irrational.

Answer:

C

Since –2 is rational and StartRoot 3 EndRoot is irrational, the sum and difference are irrational.

Step-by-step explanation:

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