Unit 2 Slope and Lines
ordered pair
(x,y)
Slope equation between two points
(y1 - y2) / (x1 - x2)
y=-2x-8 What is the slope?
-2
Standard form of a line with m = 3/2 b = -3
-3x + 2y = -6
Standard form of a line with m = 3/4 b = 2
-3x + 4y = 8
Standard form of a line with m = 4/5 b = 3
-4x + 5y = 15
y=2x-9 What is the y-intercept
-9
slope formula in standard form
-a/b
Standard form of a line with m = 1/3 b = 3
-x + 3y = 9
slope of horizontal line
0
Standard form of a line with m = -2/3 b = 0
2x + 3y = 0
Standard form of a line through (6, 0) (-9, 10)
2x + 3y = 12
Standard form of a line through (2, 0) (0, 4)
2x + y = 4
Standard form of a line with m = 2/3 b = -2
2x - 3y = 6
Standard form of a line with m = 2 b = 3
2x - y = -3
Standard form of a line with m = 2 b = -6
2x - y = 6
y=3x+2 What is the slope?
3
Standard form of a line with m = - 3/4 b = 9
3x + 4y = 36
Standard form of a line through (-2, 14) (0, 8)
3x + y = 8
Standard form of a line through (-8, -15) (-2, -6)
3x - 2y = 6
Standard form of a line through (0, -2) (3, 7)
3x - y = 2
Standard form of a line through (0, 12) (9, 0)
4x + 3y = 36
Standard form of a line through (10, -4) (5, 0)
4x + 5y = 20
Standard form of a line with m = 4/3 b = -4
4x - 3y = 12
y=6x+5 What is the y-intercept?
5
Standard form of a line with m = 5/2 b = 0
5x - 2y = 0
Standard form of a line through (3, -1) (4, 4)
5x - y = 16
Standard form of a line through (3, 13) (-4, -22)
5x - y = 2
Standard form of a line through (0, -8) (3, 0)
8x - 3y = 24
Slope (from a table)
Change in 'Y' over Change in 'X'
Is a point a solution of the line?
If the line goes through that point when graphed
On a table, how do you find b?
When x is zero
On a graph, how do you find b?
Where the line crosses the y axis
zero slope
a horizontal line
no slope
a vertical line
standard form
ax+by=c
y-intercept in standard form
c/b
slope
constant rate of change
y=x+5
equation of line thru (-1,4) and perpendicular to y=-x-4
y=3x-4
equation of line thru (1,-1) and parallel to y=3x+2
y=(2/5)x-(2/5)
equation of line thru (2,0) and perpendicular to y=-5x+3
y=-4x+7
equation of line thru (4,-9) and perpendicular to y=(1/4)x+2
y=5x-13
equation of line thru (4,7) and parallel to y=5x-3
y=(2/3)x-(10/3)
equation of line thru (5,0) and parallel to y=(2/3)x-4
What kind of line is: y = 4
horizontal line
y=mx+b
slope intercept equation of a line
slope of perpendicular lines
slope is opposite of the reciprocal
y=-(3/4)x-5
slope=-3/4; point (-8,1). Find the equation of line thru this point and the given slope.
y=2x-1
slope=2; point (-4,-9). Find the equation of line thru this point and the given slope.
y=5x+11
slope=5; point (-1,6). Find the equation of line thru this point and the given slope.
slope of parallel lines
slopes are equal
parallel lines
two lines that have the same slope
perpendicular lines
two lines whose slope is the opposite and the reciprocal
slope of vertical line
undefined
x-intercept
value of x when y = 0
y-intercept
value of y when x = 0
What kind of line is: x = 3
vertical line
What is the y-intercept
where the line crosses the 'y' axis
Standard form of a line with m = -1 b = 5
x + y = 5
Standard form of a line with m = 1/2 b = -3
x - 2y = 6
Standard form of a line with m = 1 b = -4
x - y = 4
Standard form of a line through (-2, -9) (3, -4)
x - y = 7
example of "y in terms of x"
y = 3x + 7
slope - intercept form
y = mx + b (m = slope, b = y-intercept)
b = (what does b stand for)
y-intercept
point - slope form
y-y1 = m (x - x1)
Slope (in words)
Rise over Run
m = (what does m stand for)
Slope
y=-2x+23
Slope=-2; point (10,3). Find the equation of line thru this point and the given slope.
y=7x-17
Slope=7; point(2,-3). Find the equation of line thru this point and the given slope.
