Consider this system of inequalities:

[tex]\[
\begin{array}{l}
x+y \leq -3 \\
y \ \textless \ \frac{x}{2}
\end{array}
\][/tex]

Which graph shows the solution for this system?



Answer :

To find the solution to the system of inequalities
[tex]\[ \begin{cases} x + y \le -3 \\ y < \frac{x}{2} \end{cases} \][/tex]
we need to graph both inequalities and identify the region where both conditions are satisfied.

### Step 1: Graph the inequality [tex]\(x + y \le -3\)[/tex]

1. Rewrite the inequality in slope-intercept form [tex]\(y \le -x - 3\)[/tex].
2. The equality [tex]\(y = -x - 3\)[/tex] is a straight line with a slope of -1 and a y-intercept of -3.

To graph this:
- The y-intercept is the point [tex]\((0, -3)\)[/tex].
- The slope of -1 means that for every unit increase in [tex]\(x\)[/tex], [tex]\(y\)[/tex] decreases by 1.

Plot another point by changing [tex]\(x\)[/tex]. For example:
- If [tex]\(x = 1\)[/tex], then [tex]\((1, -4)\)[/tex].

Draw the line passing through these points. As the inequality is [tex]\(\le\)[/tex], we fill in the region below and including the line.

### Step 2: Graph the inequality [tex]\(y < \frac{x}{2}\)[/tex]

1. Rewrite the inequality in slope-intercept form (it's already there) [tex]\(y < \frac{x}{2}\)[/tex].
2. The equality [tex]\(y = \frac{x}{2}\)[/tex] is a straight line with a slope of [tex]\( \frac{1}{2} \)[/tex] and a y-intercept of 0.

To graph this:
- The y-intercept is the point [tex]\((0, 0)\)[/tex].
- The slope [tex]\(1/2\)[/tex] means that for every unit increase in [tex]\(x\)[/tex], [tex]\(y\)[/tex] increases by 0.5.

Plot another point by changing [tex]\(x\)[/tex]. For example:
- If [tex]\(x = 2\)[/tex], then [tex]\((2, 1)\)[/tex].

Draw the line passing through these points. Since the inequality is [tex]\(<\)[/tex], we fill in the region below the line with a dashed line to show that the line itself is not included.

### Step 3: Identify the solution region

The solution region for the system of inequalities is the overlap of the two shaded regions from Steps 1 and 2:

- The region below the line [tex]\(y = -x - 3\)[/tex] (including the line).
- The region below the line [tex]\(y = \frac{x}{2}\)[/tex] (not including the line itself).

### Step 4: Sketch the combined graph

- Draw the line [tex]\(y = -x - 3\)[/tex], shading the region below it.
- Draw the line [tex]\(y = \frac{x}{2}\)[/tex] (with a dashed line), shading the region below it.
- The intersection (overlap) of these two shaded regions is the solution to the system.

Here's what the final graph should look like:

1. A solid line for [tex]\(y = -x - 3\)[/tex] with the region below it shaded.
2. A dashed line for [tex]\(y = \frac{x}{2}\)[/tex] with the region below it shaded.
3. The solution region is where the two shaded areas overlap. It's effectively the area below [tex]\(y = -x - 3\)[/tex] and simultaneously below or to the left of [tex]\(y = \frac{x}{2}\)[/tex].

By following these steps, you can accurately graph and find the solution region for the given system of inequalities.