Lesson 2-1
Write the slope-intercept form of a line.
y = mx + b
Write the point-slope form of a line.
y - y1 = m(x - x1)
Write the standard form of a line.
Ax + By = C
What do two parallel lines have to share?
A slope.
Given the slope of a line, how do you find the slope of the line that's perpendicular?
Find the opposite reciprocal of the slope.
What is the slope of the line through points (2, 5) and (4, 2)?
m = -3/2
Graph the following line:
y - 4 = 1/3(x - 2)
Point: (2, 4)
Slope: 1/3
Plot points: (2, 4) and (3, 7) or (1, 1)
Find the x-intercept of the following line.
4x - 10y = 20
x = 5
(5, 0)
What is the slope of the line parallel to y = 9x -15?
m = 9
What is the slope of the line perpendicular to the line y = -5/4x -12?
m = 4/5
What is the equation of the line in slope-intercept form with slope -2 and y-intercept 3.
y = -2x + 3
Write the equation of the line in point-slope form through point (-5, 4) with slope 1/3.
y - 4 = 1/3(x + 5)
Find the y-intercept of the following line:
5x + 7y = 49
y = 7
(0, 7)
Find the line parallel to y = 2x + 5 that goes through point (3, 10). Put the answer in slope-intercept or point-slope form.
y = 2x + 4
y - 10 = 2(x - 3)
Find the line perpendicular to y = 1/2x + 6 through point (4, 3).
y = -2x + 11
y - 3 = -2(x - 4)
Find the y-intercept of a line with slope -1/3 through point (3, 2).
b = 3
Write the equation of the line in point-slope form through the points (9, 2) and (7, -4).
y - 2 = 3(x - 9)
y + 4 = 3(x - 7)
If the x-intercept is (4, 0) and the y-intercept is (0, 8) and C = 16, find A and B.
A = 4
B = 2
4x + 2y = 16
Find the equation of the line parallel to y = -4x + 50 through point (1, -8). Use slope-intercept form.
y = -4x - 4
Find the equation of the line perpendicular to y = -7x - 14 through the point (14, -6). Use slope-intercept form.
y = 1/7x - 8
What is the equation of the line in slope-intercept form through points (6, 3) and (5, 8)?
y = -5x + 33
Write the equation of the line in point-slope form through the points (-3, 7) and (2, 2).
y - 7 = -(x + 3)
y - 2 = -(x - 2)
Given (0, -6) and (2, 0) write the equation of the line in standard form.
6x - 2y = 12
Find the equation of the line parallel to y = 7x + 29 through point (-3, -10). Use point-slope form.
y + 10 = 7(x + 3)
Find the equation of the line perpendicular to y = 4/5x - 27 through (-16, 10). Use point-slope form.
y - 10 = -5/4(x + 16)