A smaller number is 3 less than half a larger number. The larger number is 10 times 1 less than the smaller number. Let x represent the smaller number, and let y represent the larger number. Which equations can be used to model the situation? Check all that apply.

x = one-half y minus 3
2 x minus y = negative 6
2 x minus y = negative 3
x = one-half (y minus 3)
y = 10 (x minus 1)

1 answer

To model the situation with the given descriptions, we need to translate the statements into mathematical equations.

  1. "A smaller number is 3 less than half a larger number." This can be expressed as: \[ x = \frac{1}{2}y - 3 \]

  2. "The larger number is 10 times 1 less than the smaller number." This translates to: \[ y = 10(x - 1) \]

Now let's check the equations that you provided to see which ones correspond to these statements:

  1. \( x = \frac{1}{2}y - 3 \) - This is correct.

  2. \( 2x - y = -6 \) - This is not equivalent to either of our derived equations from the problem.

  3. \( 2x - y = -3 \) - This is not equivalent to either of our derived equations from the problem.

  4. \( x = \frac{1}{2}(y - 3) \) - This does not match our description directly, as it implies a different relationship.

  5. \( y = 10(x - 1) \) - This is correct.

Thus, the equations that can be used to model the situation are:

  • \( x = \frac{1}{2}y - 3 \)
  • \( y = 10(x - 1) \)