1. **State the problem:** We have two equations:
$$x = 4y + 8$$
and
$$y = 2x + 12$$
We want to find the values of $x$ and $y$ that make both equations true at the same time.
2. **Rewrite the first equation to express $y$ in terms of $x$:**
$$x = 4y + 8$$
Subtract 8 from both sides:
$$x - 8 = 4y$$
Divide both sides by 4:
$$y = \frac{\cancel{x - 8}}{\cancel{4}} = \frac{x - 8}{4}$$
3. **Substitute this expression for $y$ into the second equation:**
$$y = 2x + 12$$
Replace $y$ with $\frac{x - 8}{4}$:
$$\frac{x - 8}{4} = 2x + 12$$
4. **Solve for $x$:**
Multiply both sides by 4 to get rid of the denominator:
$$x - 8 = 4(2x + 12)$$
Simplify the right side:
$$x - 8 = 8x + 48$$
5. **Get all $x$ terms on one side and constants on the other:**
Subtract $x$ from both sides:
$$-8 = 7x + 48$$
Subtract 48 from both sides:
$$-8 - 48 = 7x$$
$$-56 = 7x$$
6. **Divide both sides by 7 to solve for $x$:**
$$\frac{\cancel{-56}}{\cancel{7}} = x$$
$$x = -8$$
7. **Find $y$ by substituting $x = -8$ back into $y = \frac{x - 8}{4}$:**
$$y = \frac{-8 - 8}{4} = \frac{-16}{4} = -4$$
**Final answer:**
$$x = -8, \quad y = -4$$
These values satisfy both equations.
Solve Linear System F72Af6
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