Mathematical+Reflections,+p+52

May,28,2009
 * __Mathematical Reflections 3 p.52__ Hah

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 for solving questions about linear situations are, with a graphing calculator you just put in the coordinates and you get the answer; so you don’t have to do the math yourself. Some disadvantages of using a graphing calculator for solving questions about linear situations are, when you use a graphing calculator the calculator does all the work for you. The math that it takes to get the answer helps you learn. So, with a calculator, you aren’t doing that math.


 * 2.) Explain how to find the y-intercept of a linear relationship from a table, from a graph, and from an equation.**

You can find it on a graph if the line goes over the y axis. You can find it in an equation if the equation has the letter b in it which represents (0,b), which is the y intercept. You can find it in a graph if the graph equals (0,b).


 * 3.) In Investigation 2, 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 now about the graph of a linear equation of the form y = mx + b.**

The graph of the linear equation y = mx + b is a y intercept. Meaning that the answer is on the y axis. With this equation the answer is (0,3), the 3 is on the y axis and there is nothing on the x axis hence the 0. The y intercept means that the answer is only on the y axis.


 * 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, 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 it is easy to see the order in which you did your calculations.**

You can check your work by using equations.

y= 5 – 4x (-2,13) y= 5 -4 -2 y= 5 - -8 y = 13