slope. what does slope measure? slope measures the steepness of a line
Post on 04-Jan-2016
Embed Size (px)
What does slope measure?Slope measures the steepness of a line.
What are the different types of slope?PositiveNegative
What are the different types of slope? (continued)ZeroUndefined
Formulas to find slopeSlope = RISE RUNVertical Change Horizontal Change=Change in yChange in x
What is slope?Slope is the rate of change of a line.How would you make a graph based on the following story problem?In 1970 there were 160 African American women in elected public office in the United States. By 1993 the number had increased to 2332.
African American Women in GovernmentYears19701993Number of Women
How do we find the actual slope of this line?In 1970 there were 160 African American women in elected public office in the United States. By 1993 the number had increased to 2332.What two points can we use plot the line on the coordinate plane?We have:(1970, 160)(1993, 2332)This is how we knew to put years on the x-axis and number of women on the y-axis.
Finding the slope when given two pointsWe established these points:(1970, 160)(1993, 2332)Our equation would be:2332-1601993-1970
2172 or 94 23
Change in yChange in x
y2 y1 x2 x1
In conclusionThis means that each year between 1970 and 1993, approximately 94 more African American women worked in government.The rate of change was.
Practice ProblemFind the slope between the following two points on a line:(2, 3) and (4, 6)
(x1, y1) is (2, 3) and (x2, y2) is (4, 6)
6-(-3) = 9
4-(-2) = 6
9/6 = 3/2
Slope of the line with points (-2, -3) and (4, 6) is 3/2.
Key VocabularySlopeWe use the variable m to identify slope in the equation of a line.What is slope?Y-interceptThis is the point at which the line crosses the y-axis.We use the variable b to identify the y-intercept in the equation of a line.
Equation in slope-intercept formy = mx + bA point on the line
Practice ProblemName the slope and y-intercept of the graph to the right.
m = 9/4b = 8
Equation of the line:y = 9/4x + 8
Find the slope between the following points(-2, -2) and (-4, 1)(0, 0) and (4, -2)(3, -6) and (2, -1)(4, 2) and (0, 5)(-2, -3) and (2, 4)