Geometry
Notes
Name_________________________
Warm Up
1. If you have a set of parallel lines cut by a transversal, what do you know about…
- Corresponding angles?
- Alternate interior angles?
- Alternate exterior angles?
- Consecutive interior angles?
Find the value of x.
2.
3.
(2x + 20)
81
3x
(7x + 15)
Today, we will write and graph lines
And, you will understand and apply the properties of perpendicular lines.
Writing and Graphing Equations of Lines
SLOPE INTERCEPT FORM
STANDARD FORM
Examples
Find the equation of the line.
1. m = –4, b = 2
2. m =
1
, b = –3
7
3. Write the equation of the line that has a slope of 4 and goes through the point (5, 4).
4. Put your answer to #3 in standard form.
5. Write the equation of the line that has a slope of 0 and goes through the point (–13, 8).
y
6. Write the equation of the line shown in slope-intercept form.
4
2
-4
-2
2
4
x
-2
-4
7. Write the equation of the line that goes through the point (–1, 1) and is parallel to y = 2x – 3.
8. Write the equation of a line that goes through the point (2, 3) and is perpendicular to y = –2x + 2.
9. Graph 3x + 4y = 12.
10. Write the equation of the line that goes through (0, 5) and (8, –10).
Perpendicular Lines
Fill in the blank.
1. If two lines intersect to form a linear pair of congruent angles, then the lines are
_______________________________.
2. If two lines are perpendicular, then they intersect to form four
__________________________.
3. If two sides of two adjacent acute angles are perpendicular, then the angles are
_______________.
4. If a transversal is perpendicular to one of two parallel lines, then it is ______________ to
the other.
5. In a plane, if two lines are perpendicular to the same line, then they are __________ to
each other.
Find the value of x.
6.
7.
x
x
51
3x
8.
x
(8x + 9)