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

1.
[tex]\[
\left\{
\begin{array}{l}
y = 3x - 3 \\
y = x^2 + 5x - 2
\end{array}
\right.
\][/tex]
(-1 [tex]$\square$[/tex], -6 [tex]$\square$[/tex] none [tex]$\square$[/tex], none)

2.
[tex]\[
\left\{
\begin{array}{l}
y = -2x - 7 \\
y = x^2 + 4x - 2
\end{array}
\right.
\][/tex]
([tex]$\square$[/tex], [tex]$\square$[/tex]) ([tex]$\square$[/tex], -5)

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



Answer :

Let's solve each system of equations step-by-step:

### System 1
[tex]\[ \begin{cases} y = 3x - 3 \\ y = x^2 + 5x - 2 \end{cases} \][/tex]

Equate [tex]\( 3x - 3 \)[/tex] to [tex]\( x^2 + 5x - 2 \)[/tex]:

[tex]\[ 3x - 3 = x^2 + 5x - 2 \][/tex]

Rearrange to form a standard quadratic equation:

[tex]\[ 0 = x^2 + 5x - 2 - 3x + 3 \\ 0 = x^2 + 2x + 1 \][/tex]

Solve [tex]\( x^2 + 2x + 1 = 0 \)[/tex]:

[tex]\[ (x + 1)^2 = 0 \implies x = -1 \][/tex]

Substitute [tex]\( x = -1 \)[/tex] back into [tex]\( y = 3x - 3 \)[/tex]:

[tex]\[ y = 3(-1) - 3 = -3 - 3 = -6 \][/tex]

So, the solution is [tex]\((-1, -6)\)[/tex].

### System 2
[tex]\[ \begin{cases} y = -2x - 7 \\ y = x^2 + 4x - 2 \end{cases} \][/tex]

Equate [tex]\(-2x - 7\)[/tex] to [tex]\(x^2 + 4x - 2\)[/tex]:

[tex]\[ -2x - 7 = x^2 + 4x - 2 \][/tex]

Rearrange to form a standard quadratic equation:

[tex]\[ 0 = x^2 + 4x - 2 + 2x + 7 \\ 0 = x^2 + 6x + 5 \][/tex]

Solve [tex]\( x^2 + 6x + 5 = 0 \)[/tex]:

[tex]\[ (x + 5)(x + 1) = 0 \implies x = -5 \text{ or } x = -1 \][/tex]

Substitute [tex]\( x = -5 \)[/tex] into [tex]\( y = -2x - 7 \)[/tex]:

[tex]\[ y = -2(-5) - 7 = 10 - 7 = 3 \implies (-5, 3) \][/tex]

Substitute [tex]\( x = -1 \)[/tex] into [tex]\( y = -2x - 7 \)[/tex]:

[tex]\[ y = -2(-1) - 7 = 2 - 7 = -5 \implies (-1, -5) \][/tex]

So, the solutions are [tex]\((-5, 3)\)[/tex] and [tex]\((-1, -5)\)[/tex].

### System 3
[tex]\[ \begin{cases} y = 2x - 7 \\ y = x^2 + 3x - 1 \end{cases} \][/tex]

Equate [tex]\( 2x - 7 \)[/tex] to [tex]\( x^2 + 3x - 1 \)[/tex]:

[tex]\[ 2x - 7 = x^2 + 3x - 1 \][/tex]

Rearrange to form a standard quadratic equation:

[tex]\[ 0 = x^2 + 3x - 1 - 2x + 7 \\ 0 = x^2 + x + 6 \][/tex]

Solve [tex]\( x^2 + x + 6 = 0 \)[/tex]:

The discriminant of this quadratic equation is:

[tex]\[ D = b^2 - 4ac = 1^2 - 4(1)(6) = 1 - 24 = -23 \][/tex]

Since the discriminant is negative, there are no real roots. The solutions are complex numbers:

[tex]\[ x = \frac{-1 \pm \sqrt{-23}}{2} = \frac{-1 \pm \sqrt{23}i}{2} \][/tex]

For [tex]\(x = \frac{-1 - \sqrt{23}i}{2}\)[/tex]:

[tex]\[ y = 2\left(\frac{-1 - \sqrt{23}i}{2}\right) - 7 = -1 - \sqrt{23}i - 7 = -8 - \sqrt{23}i \implies \left( \frac{-1 - \sqrt{23}i}{2}, -8 - \sqrt{23}i \right) \][/tex]

And for [tex]\(x = \frac{-1 + \sqrt{23}i}{2}\)[/tex]:

[tex]\[ y = 2\left(\frac{-1 + \sqrt{23}i}{2}\right) - 7 = -1 + \sqrt{23}i - 7 = -8 + \sqrt{23}i \implies \left( \frac{-1 + \sqrt{23}i}{2}, -8 + \sqrt{23}i \right) \][/tex]

The complex solutions are:

[tex]\[ \left( \frac{-1 - \sqrt{23}i}{2}, -8 - \sqrt{23}i \right) \\ \left( \frac{-1 + \sqrt{23}i}{2}, -8 + \sqrt{23}i \right) \][/tex]

In summary:

### Solutions

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

[tex]\((-1, -6)\)[/tex]

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

[tex]\((-5, 3)\)[/tex], [tex]\((-1, -5)\)[/tex]

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

[tex]\(\left( \frac{-1 - \sqrt{23}i}{2}, -8 - \sqrt{23}i \right)\)[/tex], [tex]\(\left( \frac{-1 + \sqrt{23}i}{2}, -8 + \sqrt{23}i \right)\)[/tex]

Thus, the final entries for the respective blanks are:

[tex]\[-1, -6, none, none\][/tex]

[tex]\[-5, 3\][/tex], [tex]\[-1, -5\][/tex]

[tex]\(\left( \frac{-1 - \sqrt{23}i}{2}, -8 - \sqrt{23}i \right)\)[/tex], [tex]\(\left( \frac{-1 + \sqrt{23}i}{2}, -8 + \sqrt{23}i \right)\)[/tex]