Linear Graph
1. **State the problem:** We need to plot the graph of the system of linear equations:
$$y - 2x = 5$$
$$2y + x = 0$$
2. **Rewrite each equation in slope-intercept form $y = mx + b$ for easier graphing:**
For the first equation:
$$y - 2x = 5 \Rightarrow y = 2x + 5$$
For the second equation:
$$2y + x = 0 \Rightarrow 2y = -x \Rightarrow y = -\frac{1}{2}x$$
3. **Interpretation:**
- The first line has slope 2 and y-intercept 5.
- The second line has slope $-\frac{1}{2}$ and y-intercept 0.
4. **Graph plotting features:**
- The first line crosses the y-axis at (0,5) and rises 2 units for every 1 unit run.
- The second line passes through the origin and falls 1 unit vertically for every 2 units traveled horizontally.
5. **Finding the point of intersection (solution to the system):**
From $y = 2x + 5$ and $y = -\frac{1}{2}x$, set equal:
$$2x + 5 = -\frac{1}{2}x$$
Multiply both sides by 2 to clear the fraction:
$$4x + 10 = -x$$
Add $x$ to both sides:
$$5x + 10 = 0$$
Subtract 10 from both sides:
$$5x = -10$$
Divide both sides by 5:
$$x = -2$$
Substitute back to find $y$:
$$y = 2(-2) + 5 = -4 + 5 = 1$$
6. **Conclusion:** The lines intersect at $(-2, 1)$.