Mathematical+Reflections,+p+52+10-11

AM May 28,2011 7D

Big idea:

Many real world situations can be modeled and predicted using mathematics.

**Mathematical Reflection 3**
__1. What are some of the advantages and disadvantages of using a graphing calculator to answer questions about linear situations?__

Some advantages of using a graphing calculator is you don't have to do any hand work or even think that much and with the graphing calculator you can just time in the coordinate or amount you want and it will find it for you. A disadvantage of using a graphing calculator is that before you can create the graph or table you have to find out the equation and you need to be familiar with equations to do it.  __2. Explain how to find the y-intercept of a linear relationship from a table, from a graph, and from and equation.__

On at table when x equals 0 the while value equals the y-intercept. On a graph it's when the line crosses the y-axis hence the y-intercept. In an equation the y intercept is represented as the variable b, and it comes at the end of the equation.

__3. In Investigation2, you explored the effect that the rate has on the graph of a linear relationship. In this investigation, you looked at the meaning of particular points on the graph, including the y-intercept. Summarize what you know about the graph of a linear equation of the form y= mx+b.__

In the equation y stands as the solution. The answer depending on the other stuff inside the equation. Y is the dependent variable. It is the information that helps place the information that helps place the information on the graph. The variable m is the slope, which is the steepness of the graph. It is also the coefficient of x. The variable x is the value of x which m is multiplied by. X is the Independent variable. Finally there is the variable b that stands for the y-intercept which on the graph is the place on the y-axis where the line crosses. 

4. To check whether a given point fits a linear relationship, you can make a table, trace a graph, or substitute the coordinates into an equation. When you substitute values into an equation, you need to be careful about the order in which you do the calculations. Check whether the point (-2, 13) is on the line y= 5-4x by substituting the coordinates into the equation. Show and explain each step you take so that is easy to see the order in which you did your calculations.

You would write the equation and then re-write it in y= -3 the answer is: y= 5-4x y= 5-(-8) y= 5-4-2 y=13

Summary
In this investigation we learned about graphing calculators. We learned that there are advantages and disadvantages to them. We learned how to find the y-intercept in a graph, table, and equation. We also learned what each variable in a linear equation meant and how they related to the graph.