Instructions: Solve the following systems of equations algebraically. If there are no real solutions, type "none" in both blanks. If there is only one, type "none" in the other blank.

1.
[tex]\[
\begin{cases}
y = 3x - 3 \\
y = x^2 + 5x - 2
\end{cases}
\][/tex]
( [tex]$\square$[/tex] , [tex]$\square$[/tex] )

2.
[tex]\[
\begin{cases}
y = -2x - 7 \\
y = x^2 + 4x - 2
\end{cases}
\][/tex]
( [tex]$\square$[/tex] , [tex]$\square$[/tex] )

3.
[tex]\[
\begin{cases}
y = 2x - 7 \\
y = x^2 + 3x - 1
\end{cases}
\][/tex]
( [tex]$\square$[/tex] , [tex]$\square$[/tex] )



Answer :

Let's solve the given systems of equations algebraically.

First System:
[tex]\[ \left\{\begin{array}{l} y = 3x - 3 \\ y = x^2 + 5x - 2 \end{array}\right. \][/tex]

To find the points of intersection, set the equations equal to each other:
[tex]\[ 3x - 3 = x^2 + 5x - 2 \][/tex]

Rearrange the equation to set it to zero:
[tex]\[ x^2 + 5x - 2 - 3x + 3 = 0 \\ x^2 + 2x + 1 = 0 \][/tex]

Factor the quadratic equation:
[tex]\[ (x + 1)^2 = 0 \][/tex]

This gives:
[tex]\[ x = -1 \][/tex]

Plug [tex]\(x = -1\)[/tex] back into the first equation [tex]\(y = 3x - 3\)[/tex]:
[tex]\[ y = 3(-1) - 3 = -6 \][/tex]

So, the solution for the first system is:
[tex]\[ (-1, -6) \][/tex]

Second System:
[tex]\[ \left\{\begin{array}{l} y = -2x - 7 \\ y = x^2 + 4x - 2 \end{array}\right. \][/tex]

Set the equations equal to each other:
[tex]\[ -2x - 7 = x^2 + 4x - 2 \][/tex]

Rearrange the equation to set it to zero:
[tex]\[ x^2 + 4x - 2 + 2x + 7 = 0 \\ x^2 + 6x + 5 = 0 \][/tex]

Factor the quadratic equation:
[tex]\[ (x + 1)(x + 5) = 0 \][/tex]

This gives:
[tex]\[ x = -1 \quad \text{or} \quad x = -5 \][/tex]

For [tex]\(x = -1\)[/tex]:
[tex]\[ y = -2(-1) - 7 = -5 \][/tex]

For [tex]\(x = -5\)[/tex]:
[tex]\[ y = -2(-5) - 7 = 3 \][/tex]

So, the solutions for the second system are:
[tex]\[ (-5, 3) \quad \text{and} \quad (-1, -5) \][/tex]

Third System:
[tex]\[ \left\{\begin{array}{l} y = 2x - 7 \\ y = x^2 + 3x - 1 \end{array}\right. \][/tex]

Set the equations equal to each other:
[tex]\[ 2x - 7 = x^2 + 3x - 1 \][/tex]

Rearrange the equation to set it to zero:
[tex]\[ x^2 + 3x - 1 - 2x + 7 = 0 \\ x^2 + x + 6 = 0 \][/tex]

This quadratic equation has no real solutions, as its discriminant is negative:
[tex]\[ \Delta = 1^2 - 4(1)(6) = 1 - 24 = -23 \][/tex]

The solutions to this quadratic are complex (non-real):
[tex]\[ x = \frac{-1 \pm \sqrt{-23}}{2} = \frac{-1 \pm \sqrt{23}i}{2} \][/tex]

Thus, the points of intersection (in terms of complex numbers) are:
[tex]\[ \left(-\frac{1}{2} - \frac{\sqrt{23}i}{2}, -8 - \sqrt{23}i\right) \quad \text{and} \quad \left(-\frac{1}{2} + \frac{\sqrt{23}i}{2}, -8 + \sqrt{23}i\right) \][/tex]

Therefore, summarizing the solutions for each system:

[tex]\[ \left\{\begin{array}{l} y = 3x - 3 \\ y = x^2 + 5x - 2 \end{array}\right. \Rightarrow (-1, -6) \][/tex]

[tex]\[ \left\{\begin{array}{l} y = -2x - 7 \\ y = x^2 + 4x - 2 \end{array}\right. \Rightarrow (-5, 3) \; \text{and} \; (-1, -5) \][/tex]

[tex]\[ \left\{\begin{array}{l} y = 2x - 7 \\ y = x^2 + 3x - 1 \end{array}\right. \Rightarrow \left(-\frac{1}{2} - \frac{\sqrt{23}i}{2}, -8 - \sqrt{23}i\right) \; \text{and} \; \left(-\frac{1}{2} + \frac{\sqrt{23}i}{2}, -8 + \sqrt{23}i\right) \][/tex]

Given the required forms:
[tex]\[ ( (-1, -6), (-5, 3), (-1, -5), \left(-\frac{1}{2} - \frac{\sqrt{23}i}{2}, -8 - \sqrt{23}i\right), \left(-\frac{1}{2} + \frac{\sqrt{23}i}{2}, -8 + \sqrt{23}i\right) ) \][/tex]