Day 2

Daily Objective: Students will write linear equation of a line using data

The linear equation is an equation that makes a straight line when it is graphed.

Often written in the form: y = mx+b

A linear equation is in the form y=mx+b. So do find that equation we need a graph.

For this example we will use this graph:















Now that we have a graph we need to pick 2 points on the line of best fit. We will use (10,8) and (14,10). In the form y=mx+b, the m is the slope. To find slope we need to do y2 - y1.

                                                                                                                         x1 - x2

So with our points it would look like 10-8.

                                                          14-10

that will give us 2 or 1 .

                        4     2

So now we have in our linear equation: y=1/2x+b. to find the b in the equation we use one point. We will use (10,8). we plug it into our equation. 8 is the y and 10 is the x.

it looks like 8=1/2(10)+b. now you times 10 by 1/2 and get 5. Now you subtract the 5 from both sides and 8-5= 3. Now you have 3=b which is your b.

Now you have your linear equation which is y=1/2x+3.

Questions:

1.) Find the equation of  graph with the points (10,2) and (5,6).

2.) What does the m stand for is the linear equation form of y=mx+b?

3.) how do you find the b part in the linear equation y=mx+b?

Answers:

1.)

2.) The m stands for the slope

3.) To find the b you need the slope. you take an equation and put the y and the x where it is in the equation. than you times the slope by x and than either add or subtract to make whatever the answer is to be 0. than you add or subtract that to your y and there's your b part.