IDNLearn.com offers a user-friendly platform for finding and sharing answers. Receive prompt and accurate responses to your questions from our community of knowledgeable professionals ready to assist you at any time.

Select the correct answer.

For which system of inequalities is [tex]$(3,-7)$[/tex] a solution?

A.
[tex]\[
\begin{array}{l}
x + y \ \textless \ -4 \\
3x + 2y \ \textless \ -5
\end{array}
\][/tex]

B.
[tex]\[
\begin{array}{l}
x + y \leq -4 \\
3x + 2y \ \textless \ -5
\end{array}
\][/tex]

C.
[tex]\[
\begin{array}{l}
x + y \ \textless \ -4 \\
3x + 2y \leq -5
\end{array}
\][/tex]

D.
[tex]\[
\begin{array}{l}
x + y \leq -4 \\
3x + 2y \leq -5
\end{array}
\][/tex]


Sagot :

To determine which system of inequalities [tex]\((3, -7)\)[/tex] is a solution for, we will evaluate each system step-by-step.

### System A:
1. [tex]\(x + y < -4\)[/tex]
- Substitute [tex]\(x = 3\)[/tex] and [tex]\(y = -7\)[/tex]
- [tex]\(3 + (-7) = -4\)[/tex]
- Check: [tex]\(-4 < -4\)[/tex] (False)

2. [tex]\(3x + 2y < -5\)[/tex]
- Substitute [tex]\(x = 3\)[/tex] and [tex]\(y = -7\)[/tex]
- [tex]\(3(3) + 2(-7) = 9 - 14 = -5\)[/tex]
- Check: [tex]\(-5 < -5\)[/tex] (False)

Both inequalities must be true for the system to be true. Since the first condition is false, [tex]\( (3, -7) \)[/tex] does not satisfy system A.

### System B:
1. [tex]\(x + y \leq -4\)[/tex]
- Substitute [tex]\(x = 3\)[/tex] and [tex]\(y = -7\)[/tex]
- [tex]\(3 + (-7) = -4\)[/tex]
- Check: [tex]\(-4 \leq -4\)[/tex] (True)

2. [tex]\(3x + 2y < -5\)[/tex]
- Substitute [tex]\(x = 3\)[/tex] and [tex]\(y = -7\)[/tex]
- [tex]\(3(3) + 2(-7) = 9 - 14 = -5\)[/tex]
- Check: [tex]\(-5 < -5\)[/tex] (False)

Both inequalities must be true for the system to be true. Since the second condition is false, [tex]\( (3, -7) \)[/tex] does not satisfy system B.

### System C:
1. [tex]\(x + y < -4\)[/tex]
- Substitute [tex]\(x = 3\)[/tex] and [tex]\(y = -7\)[/tex]
- [tex]\(3 + (-7) = -4\)[/tex]
- Check: [tex]\(-4 < -4\)[/tex] (False)

2. [tex]\(3x + 2y \leq -5\)[/tex]
- Substitute [tex]\(x = 3\)[/tex] and [tex]\(y = -7\)[/tex]
- [tex]\(3(3) + 2(-7) = 9 - 14 = -5\)[/tex]
- Check: [tex]\(-5 \leq -5\)[/tex] (True)

Both inequalities must be true for the system to be true. Since the first condition is false, [tex]\( (3, -7) \)[/tex] does not satisfy system C.

### System D:
1. [tex]\(x + y \leq -4\)[/tex]
- Substitute [tex]\(x = 3\)[/tex] and [tex]\(y = -7\)[/tex]
- [tex]\(3 + (-7) = -4\)[/tex]
- Check: [tex]\(-4 \leq -4\)[/tex] (True)

2. [tex]\(3x + 2y \leq -5\)[/tex]
- Substitute [tex]\(x = 3\)[/tex] and [tex]\(y = -7\)[/tex]
- [tex]\(3(3) + 2(-7) = 9 - 14 = -5\)[/tex]
- Check: [tex]\(-5 \leq -5\)[/tex] (True)

Both inequalities are true. Therefore, [tex]\((3, -7)\)[/tex] satisfies system D.

### Conclusion:
The point [tex]\((3, -7)\)[/tex] is a solution to system D.
So, the correct answer is:
D.
[tex]\[ \begin{array}{l} x+y \leq-4 \\ 3 x+2 y \leq-5 \end{array} \][/tex]