Grade 10 - Linear Models

Today we will take up any problems from the handout from yesterday. Especially focusing on #5, and 8.
We will continue determining the equation of the line, using two points on a line and applying y2-y1/x2-x1.

Ex. 1: A line with slope 2 passes through the point (4,3). Determine the equation of the line.
Solution: m = 2
y = 2x + b (solve b)
plug in the value x = 4 and y = 3
3 = 2(4) + b
3 = 8 + b
3 - 8 = b (subtract 8 from both sides)
-5 = b
Therefore, y = 2x -5

Ex. 2: Given the points (-1,4) and (5,13). Determine the equation of the line.
M=y2-y1/x2-x1
=13-4/5-(-1)
= 9/6
= 3/2
Then to figure out the b value, we must use y=mx + b and substitute what we know.
y = 3/2x + b
pick one of the two points and plug in the values. Picking the 1st point, (-1,4) we get 4 = 3/2(-1) + b and then we can solve for b.
4 = -3/2 + b
4 + 3/2 = b (add 3/2 to both sides)
8/2 + 3/2 = b (make a common denominator, if you use your calculator at this step that is okay)
11/2 = b
Therefore, the equation of the line is y = 3/2x + 11/2

Using the handout supplied in class, complete #1 ac, 2ac, 3ac, 5aceg, 6all, 7ace
I will be doing a homework check tomorrow. I am available at lunchtime if you require some help.
Mrs. Gascho