Equations of lines
Given two points writing the equation of a line
Slope intercept
Point Slope of a line
1. Find the slope
2. Calculate the y-int
Substitute in the slope and one set of ordered pairs (x,y) you should them be able to solve for b
3. Write the equation of a line
Parallel Lines - slopes are the same need to calculate a new y-int
Sub in same slope, sub in different x and y values and solve for new b
Perpendicular lines - slopes are opposite reciprocals, which means flip the fraction and change the sign to the opposite of what the original equation was
Perpendicular lines can have the same y-int, but you need to calculate it like all the other equations
Zero slope is a slope when the rise of the line is zero
Lines with a zero slope are horizontal
y=number
Undefined slope is a slope when the run is zero
Lines with an undefined slope are vertical
x=number
Given the following ordered pairs find the equation of the line.
(2, -5) and ( -4,7)
Given the following equation of the line find the following:
(solve the equation for y to find the slope)
1. Equation of a line parallel and through (-2,2)
Use slope and point to find b
2. Equation of a line perpendicular and through (3,-1)
Parallel Lines and Transversals
If they state lines are parallel then certain angle relationships are congruent or supplementary
Corresponding Angles - congruent
1 and 52 and 63 and 7
110 and 4
Alternate Interior Angles - congruent
3 and 52 and 4
Alternate Exterior Angles - congruent
1 and 7110 and 6
Same Side Interior Angles - supplementary
3 and 42 and 5
Knowing Shapes and what markings mean
Study the figure below. Jose believes that all of the statements about this figure must be true. Is Jose Correct? Explain why or why not for each statement.
Statement A: The figure is a quadrilateral.
Statement B: The figure is a parallelogram.
Statement C: The figure is a rectangle.
Statement D: The figure is a rhombus.
Statement E: The figure is a square.
Finding angle measure
Constructions
Part A: On your grid, draw the triangle J’K’L’, the image of triangle JKL after it has been reflected over the y-axis. Be sure to label your vertices
Part B: On your grid, draw the triangle J’’K’’L’’, the image of J’K’L’ after it has been reflected over the line y=x. Be sure to label your vertices
Construct Altitude from one vertex and median from another
Proofs - given 2 triangles congruent prove other triangles or parts congruent.
Given statements first
need 3 parts stated congruent
triangles
CPCTC
Given: