What are the exact solutions of x2 − 3x − 7 = 0? x = the quantity of 3 plus or minus the square root of 37 all over 2 x = the quantity of negative 3 plus or minus the square root of 37 all over 2 x = the quantity of 3 plus or minus the square root of 19 all over 2 x = the quantity of negative 3 plus or minus the square root of 19 all over 2

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Answer:

  (a)  x = the quantity of 3 plus or minus the square root of 37 all over 2

  [tex]x=\dfrac{3\pm\sqrt{37}}{2}[/tex]

Step-by-step explanation:

The given equation is a second-degree (quadratic) equation. Its solutions can be found using the "quadratic formula" applicable to such equations.

Quadratic formula

A quadratic equation written in standard form is ...

  [tex]ax^2+bx+c=0[/tex]

Its solutions are given by the formula ...

  [tex]x=\dfrac{-b\pm\sqrt{b^2-4ac}}{2a}[/tex]

Application

Comparing the given quadratic to the standard form, we see the coefficients are ...

  a = 1, b = -3, c = -7

Using these values in the quadratic formula gives the solutions as ...

  [tex]x=\dfrac{-(-3)\pm\sqrt{(-3)^2-4(1)(-7)}}{2(1)}=\dfrac{3\pm\sqrt{9+28}}{2}\\\\\boxed{x=\dfrac{3\pm\sqrt{37}}{2}}[/tex]

The verbal description of this expression matches the first choice.

Answer:

The exact solution is:

x = the quantity of 3 plus or minus the square root of 37 all over 2

Step-by-step explanation:

We are asked to find the exact solution of the polynomial equation which is given by:

[tex]x^2-3x-7=0[/tex]

We know that the solution of the equation are the possible value of x which is obtained on solving the equation and hence satisfy the equation.

Now, on solving the quadratic equation i.e.  degree 2 polynomial equation using the quadratic formula:

That is any polynomial equation of the type:

[tex]ax^2+bx+c=0[/tex]

is solved by using the formula:

[tex]x=\dfrac{-b\pm \sqrt{b^2-4ac}}{2a}[/tex]

Here we have:

a=1, b=-3 and c=-7.

Hence, the solution of the equation is:

[tex]x=\dfrac{-(-3)\pm \sqrt{(-3)^2-4\times (-7)\times 1}}{2\times 1}\\\\\\x=\dfrac{3\pm \sqrt{9+28}}{2}\\\\\\x=\dfrac{3\pm \sqrt{37}}{2}[/tex]

Hence, the solution is:

x = the quantity of 3 plus or minus the square root of 37 all over 2

( i.e.

[tex]x=\dfrac{3\pm \sqrt{37}}{2}[/tex]  )

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