Andrea is 6 years younger than Tony. In two years, Tony will be three times as old as Andrea. Let a be Tony’s current age. Which of these linear equations can be used to find Andrea’s and Tony’s current ages?(1 point) Responses a+2=3(a−6+2) a plus 2 equals 3 left parenthesis a minus 6 plus 2 right parenthesis a+2=3(a+6+2) a plus 2 equals 3 left parenthesis a plus 6 plus 2 right parenthesis a=3(a+2) a equals 3 left parenthesis a plus 2 right parenthesis 3(a+2)=a−6+2 3 left parenthesis a plus 2 right parenthesis equals a minus 6 plus 2

1 answer

To solve the problem, we first need to define Andrea’s age in terms of Tony’s age.

Let:

  • \( a \) = Tony’s current age
  • \( a - 6 \) = Andrea’s current age (since Andrea is 6 years younger than Tony)

In two years:

  • Tony’s age will be \( a + 2 \)
  • Andrea’s age will be \( (a - 6) + 2 = a - 4 \)

According to the problem, in two years, Tony will be three times as old as Andrea:

\[ a + 2 = 3(a - 4) \]

Now, let's simplify this equation:

\[ a + 2 = 3a - 12 \]

Rearranging gives us:

\[ a - 3a = -12 - 2 \] \[ -2a = -14 \] \[ a = 7 \]

So, Tony's current age is 7 and Andrea's age is \( 7 - 6 = 1 \).

Now, let's check the response options given:

  1. \( a + 2 = 3(a - 6 + 2) \)

    • \( a + 2 = 3(a - 4) \) (this one is correct)
  2. \( a + 2 = 3(a + 6 + 2) \)

    • This does not represent the scenario correctly.
  3. \( a = 3(a + 2) \)

    • This does not represent the scenario correctly.
  4. \( 3(a + 2) = a - 6 + 2 \)

    • This simplifies to \( 3(a + 2) = a - 4 \) (not correct)

The correct equation that can be used to find Andrea’s and Tony’s current ages is:

\( a + 2 = 3(a - 4) \), which corresponds to the first option you provided:

\( a + 2 = 3(a - 6 + 2) \) or simply the rearranged version \( a + 2 = 3(a - 4) \).