Slope-Intercept Form
What is the formula for slope-intercept form?
y = mx + b
What is the symbol for the y-intercept?
´b´
What is the symbol for slope?
´m´
DOUBLE JEOPARDY
A line passes through (-3, 7) and (9, -1). Find the slope of this line.
Remember to reduce!
m = -2/3
What does an x-intercept and y-intercept look like on a graph?
X-intercept crosses the x-axis, and the y-intercept crosses the y-axis.
What does a negative and positive slope look like on a graph?
Falling line and a rising line.
Given the following equation and the coordinate on the line, solve for b.
(sorry about the fractions formatting)
y = -3/2x + b
(-1/4, 5/8)
b = 1/4
(0, b)
If the equation is y = 2x + 3, what is the slope of a line parallel to this?
m = 2
y = mx + 7
(-5, 5)
m = 2/5
DOUBLE JEOPARDY
True or False:
If a line is linear, it can have more than one x- or y-intercept in special cases.
False, if the line is linear it can only cross each axis once.
If the equation of a line is y = -5x - 4, what is the slope of a line perpendicular to this line?
m = +1/5
Write an equation in slope-intercept form of the line that is PERPENDICULAR to the graph of each equations and passes through the given point.
7y + 4x = 3
(-4, -7)
y = 7/4 x
Using algebra, calculate the y-intercept coordinates of
x + 2y - 8 = 0.
(0,4)
Are perpendicular lines always negative reciprocals of one another? If not, provide a specific example when this is not true.
An undefined slope (vertical line) and a slope of zero (horizontal line) are perpendicular to each other, yet their slopes are not negative reciprocals.