Question
Solve the system of linear equations using substitution. 2x + y = -11 3x - 4y = 11 (1 point) Responses (5,3) (5,3) (-5,-3) (-5,-3) (3,5) (3,5) (-3,-5)
Answers
GPT-4o mini
To solve the system of linear equations using substitution, we'll follow these steps:
1. **Choose one equation to solve for one variable.** Let's solve the first equation for \(y\):
\[
2x + y = -11
\]
Rearranging gives:
\[
y = -11 - 2x \quad \text{(1)}
\]
2. **Substitute this expression for \(y\) into the second equation.** Using the second equation:
\[
3x - 4y = 11
\]
Substituting \(y\) from equation (1):
\[
3x - 4(-11 - 2x) = 11
\]
This simplifies to:
\[
3x + 44 + 8x = 11
\]
Combining like terms:
\[
11x + 44 = 11
\]
3. **Solve for \(x\):**
Subtract 44 from both sides:
\[
11x = 11 - 44
\]
\[
11x = -33
\]
Divide by 11:
\[
x = -3
\]
4. **Now substitute \(x = -3\) back into equation (1) to find \(y\):**
\[
y = -11 - 2(-3)
\]
\[
y = -11 + 6
\]
\[
y = -5
\]
5. **So, the solution to the system of equations is:**
\[
(x, y) = (-3, -5)
\]
From the given responses, the correct answer is:
\((-3, -5)\)
1. **Choose one equation to solve for one variable.** Let's solve the first equation for \(y\):
\[
2x + y = -11
\]
Rearranging gives:
\[
y = -11 - 2x \quad \text{(1)}
\]
2. **Substitute this expression for \(y\) into the second equation.** Using the second equation:
\[
3x - 4y = 11
\]
Substituting \(y\) from equation (1):
\[
3x - 4(-11 - 2x) = 11
\]
This simplifies to:
\[
3x + 44 + 8x = 11
\]
Combining like terms:
\[
11x + 44 = 11
\]
3. **Solve for \(x\):**
Subtract 44 from both sides:
\[
11x = 11 - 44
\]
\[
11x = -33
\]
Divide by 11:
\[
x = -3
\]
4. **Now substitute \(x = -3\) back into equation (1) to find \(y\):**
\[
y = -11 - 2(-3)
\]
\[
y = -11 + 6
\]
\[
y = -5
\]
5. **So, the solution to the system of equations is:**
\[
(x, y) = (-3, -5)
\]
From the given responses, the correct answer is:
\((-3, -5)\)