Which of the following equations has a solution of 1/2

5 answers

To determine which equation has a solution of \( \frac{1}{2} \), we would typically need a list of equations to evaluate. Please provide the equations you want to consider, and I'll help you find which one has a solution of \( \frac{1}{2} \).

X+1=1/2
X-1/2=1
X-1=-1/2
X+1/2=-1

Let's solve each of the equations to determine which one has a solution of \( \frac{1}{2} \).

  1. \( x + 1 = \frac{1}{2} \) \[ x = \frac{1}{2} - 1 = \frac{1}{2} - \frac{2}{2} = -\frac{1}{2} \] (Not a solution of \( \frac{1}{2} \))

  2. \( x - \frac{1}{2} = 1 \) \[ x = 1 + \frac{1}{2} = \frac{2}{2} + \frac{1}{2} = \frac{3}{2} \] (Not a solution of \( \frac{1}{2} \))

  3. \( x - 1 = -\frac{1}{2} \) \[ x = -\frac{1}{2} + 1 = -\frac{1}{2} + \frac{2}{2} = \frac{1}{2} \] (This is a solution of \( \frac{1}{2} \))

  4. \( x + \frac{1}{2} = -1 \) \[ x = -1 - \frac{1}{2} = -\frac{2}{2} - \frac{1}{2} = -\frac{3}{2} \] (Not a solution of \( \frac{1}{2} \))

Based on the evaluations, the equation \( x - 1 = -\frac{1}{2} \) has a solution of \( \frac{1}{2} \).

Mario is 12 years old. In 7 years, he will be 19. Which equation can be used to determine Mario’s present age

To determine Mario's present age based on the information provided, we can set up an equation. Let \( x \) represent Mario’s present age.

From the problem:

  • Mario is currently 12 years old.
  • In 7 years, he will be \( 12 + 7 = 19 \), which aligns with the statement that in 7 years he will be 19.

The equation to represent this situation can be set up as follows:

\[ x + 7 = 19 \]

Here, \( x \) represents Mario's present age. To solve for \( x \):

\[ x = 19 - 7 \] \[ x = 12 \]

Thus, the equation \( x + 7 = 19 \) can be used to determine Mario's present age. However, since we already know his current age is 12, the situation satisfies our equation. The equation is correct, but Mario's present age is simply \( 12 \).