To find the equation that matches the solution set of {5}, we need to evaluate each equation to see if x = 5 is a solution.
-
Equation: \( 3x + 4 = 7 \)
- Substitute \( x = 5 \): \[ 3(5) + 4 = 15 + 4 = 19 \quad (\text{not } 7) \]
- This does not match.
-
Equation: \( x + x - 9 = 1 + x \)
- Simplifying the left side: \[ 2x - 9 = 1 + x \]
- Substitute \( x = 5 \): \[ 2(5) - 9 = 10 - 9 = 1, \quad 1 + 5 = 6 \quad (\text{not equal}) \]
- This does not match.
-
Equation: \( x^2 - 10 = 15 \)
- Rearranging it gives: \[ x^2 = 25 \]
- Taking the square root: \[ x = 5 \quad \text{or} \quad x = -5 \]
- This matches one of the solutions, but not just {5}.
-
Equation: \( 2x - 20 = 30 \)
- Solve for \( x \): \[ 2x = 30 + 20 \] \[ 2x = 50 \] \[ x = 25 \quad (\text{not } 5) \]
- This does not match.
Among the equations presented, none matches the solution set of exactly {5}. However, \( x^2 - 10 = 15 \) does include 5 as one of its solutions. If the context allows for solutions, this may be the closest match.
If strictly looking for only {5}, then none of the options strictly meet that criteria.