Unit 4B – Day 4 Guided Notes Name: ______
Review: Slope-Intercept and Standard Form
l Only write equations in standard form if you are given a ______.
l Only write a word problem in standard form if you are NOT given a ______.
l Standard form word problems can only be written if you have ______.
l DO NOT write an equation in standard form if you are given the slope and y-intercept.
l That equation should be written in ______form.
1. What is the Slope-Intercept Form?
2. What is the Standard Form?
3. How does an equation of a vertical line look? What is the slope?
4. How does an equation of a horizontal line look? What is the slope?
Point-Slope Form
m =
(x1, y1) =
Best used when: you are given the ______(that is not the y-intercept) and you need to write the equation of the line.
Example: Write the equation in Point-Slope Form of the graph below if it goes through the point (-5,-4) and has a slope of 2/3:
Write an Equation in Point-Slope Form Given a Point and a Slope
2. (-1, -3); Slope = 4
3. (-10, 0); Slope = 2
4. (-4, 3); Slope = -6
Write an Equation in Point-Slope Form Given Two Points
Steps:
1. Find the ______ between the two points.
2. Pick ______to use in order to write the equation.
3. Plug in the slope and coordinate from the point into the ______
5. (-3, 6) and (1, -2)
6. (-2, 3) and (-1, 1)
7. (-2, -5) and (7, -6)
Writing an Equation from a Table
l What is the independent and dependent variable?
l Find the rate of change:
l What is the slope?
l What is one ordered pair?
l What is a possible equation in Point-Slope Form?
Slope - Int. Form / Standard Form / Point - Slope FormWriting Equations in Point-Slope Form
Given a point and the slope of a line, write the equation in point-slope form.
1) 2)
3) 4)
Given a graph of a line, first find the slope. Then choose one point on the line to be your (x1, y1). Use m and the point you chose to write the line in point-slope form.
5) 6)
7) 8)