A model is an estimate or approximation of a data set. In the real world, there are too many variables to know exactly what will happen. However, if a model is a good fit, then it can be used to make predictions about what will happen. With a useful model, a predicted value should be a good estimate of an observed value. What did you include in your response? Check all that apply. A model is an estimate of a data set. A useful model can be used to make predictions. Predictions should be a good estimate of what will actually happen.

A model is an estimate of a data set.

A useful model can be used to make predictions.

Step-by-step explanation:

There are various models used in mathematics which are used to predict variables. The regression model is used to predict the relation between two variables. There are various other models which help to predict the future events and outcome of these events.

1/5^2 = 7.56/45

7.9m and 4.3°

step-by-step explanation:

let east be +x and north be +y, x = distance * cos θ, y = distance * sin θ  

for 3.5 south, y = -3.5  

for 8.2, x = 8.2 * cos 30 and y = 8.2 * sin 30  

for 15 west, x = -15  

total x = 8.2 * cos 30 – 15 ≈ -7.9  

total y = -3.5 + 8.2 * sin 30 = 0.6  

magnitude = [(8.2 * cos 30 – 15)^2 + 0.6^2)]^0.5  

the magnitude is approximately 7.9 m  

tan θ = y/x = 0.6/-7.9  

the angle is approximately 4.3˚ north of west