Determine the values of [tex]\( x \)[/tex] that satisfy the system of equations below:

[tex]\[
\begin{array}{l}
y = x^2 + 8x - 5 \\
y = 8x - 4
\end{array}
\][/tex]



Answer :

Sure, let's solve the system of equations step by step:

[tex]\[ \begin{array}{l} 1. ~ y = x^2 + 8x - 5 \\ 2. ~ y = 8x - 4 \end{array} \][/tex]

Given these two equations, we can set them equal to each other because they both equal [tex]\( y \)[/tex]:

[tex]\[ x^2 + 8x - 5 = 8x - 4 \][/tex]

Next, we subtract [tex]\( 8x \)[/tex] from both sides of the equation to simplify:

[tex]\[ x^2 + 8x - 5 - 8x = 8x - 4 - 8x \implies x^2 - 5 = -4 \][/tex]

Then, we add 4 to both sides of the equation:

[tex]\[ x^2 - 5 + 4 = -4 + 4 \implies x^2 - 1 = 0 \][/tex]

This results in a standard quadratic equation, which we can solve by factoring:

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

Setting each factor to zero gives us the possible values for [tex]\( x \)[/tex]:

[tex]\[ x - 1 = 0 \implies x = 1 \][/tex]
[tex]\[ x + 1 = 0 \implies x = -1 \][/tex]

Now we have two values for [tex]\( x \)[/tex]. We need to find the corresponding [tex]\( y \)[/tex] values for each [tex]\( x \)[/tex], using the equation [tex]\( y = 8x - 4 \)[/tex]:

For [tex]\( x = 1 \)[/tex]:

[tex]\[ y = 8(1) - 4 = 8 - 4 = 4 \][/tex]

For [tex]\( x = -1 \)[/tex]:

[tex]\[ y = 8(-1) - 4 = -8 - 4 = -12 \][/tex]

Thus, the solutions to the system of equations are:

[tex]\[ \boxed{(-1, -12)} \text{ and } \boxed{(1, 4)} \][/tex]

So the values of [tex]\( x \)[/tex] that satisfy the system of equations are [tex]\( x = 1 \)[/tex] and [tex]\( x = -1 \)[/tex], with the corresponding [tex]\( y \)[/tex] values being [tex]\( y = 4 \)[/tex] and [tex]\( y = -12 \)[/tex], respectively.