How would you write a real-world problem that models the following equation: −x+40=x

?(1 point)
Responses

The amount of money a stock lost in the stock market was $40 more than it gained.

If Alex gained as much money as she lost, she would have 40 dollars.

Marsha is below sea level. To get as far above sea level as she is below, she would have to move to a location 40 feet higher.

The number of days that the temperature has been below zero is 40 fewer than the number of days the temperature has been above zero.

1 answer

To model the equation \( -x + 40 = x \), we can analyze the options given:

  1. The amount of money a stock lost in the stock market was $40 more than it gained. This could be represented mathematically as: \[ \text{Loss} = \text{Gain} + 40 \] This doesn't directly translate to the equation.

  2. If Alex gained as much money as she lost, she would have 40 dollars. This implies: \[ \text{Loss} + 40 = \text{Gain} \] This doesn't match the equation either.

  3. Marsha is below sea level. To get as far above sea level as she is below, she would have to move to a location 40 feet higher. If she is at position \(-x\) (below sea level), to reach zero (sea level), she would need to move up \(x\) feet, so the total distance to move to a location 40 feet higher would require: \[ -x + 40 = x \] This option fits perfectly with the equation.

  4. The number of days that the temperature has been below zero is 40 fewer than the number of days the temperature has been above zero. This can be expressed as: \[ \text{Number of days below zero} = \text{Number of days above zero} - 40 \] This does not match the equation.

Among the options provided, the best fit for modeling the equation \( -x + 40 = x \) is:

Marsha is below sea level. To get as far above sea level as she is below, she would have to move to a location 40 feet higher.