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Slope-Intercept Form
Point-Slope Form
Standard Form
Word Problems
Perpendicular Lines
100
Create an equation in slope-intercept form with a slope of -1 that goes through (0, 9)
y = -x + 9
100
Daily Double! Put in Standard Form (I know, wrong category) y = x(4 + x)
NON-LINEAR because of the exponent. Tricky tricky!
100
List the rules for standard form.
Correct order: Ax + By = C A, B, C are integers GCF of A, B, C = 1 A is positive A or B can be zero, but not both
100
Is it a direct variation? If yes, find k. If no, tell why not. Mrs. James throws away 3 dried out expo markers every week. The total # of markers she has left (y) depends on the number of weeks that have gone by (x)
no-- it is decreasing at a constant rate, but would not start at the origin because she would have to start with a certain number of markers.
100
What is the relationship between the slope of perpendicular lines?
They are opposite reciprocals. Their product is -1.
200
Write the equation of a line in slope-intercept form: m = 4, goes through (-3, 3)
y = 4x + 15
200
Write the equation of a line in point-slope form: m = 1/4, passes through (8, -2)
y + 2 = 1/4(x - 8)
200
Write the equation of the line in standard form: y = -1/3x + 3
x + 3y = 9
200
You have 30 dollars to spend on snacks for a party. Each pizza is 8 dollars and each bottle of soda is 2 dollars. Write an equation to model the number of pizzas and sodas you can buy.
8p + 2s = 30
200
What is slope of the line perpendicular to: y = 4x - 10
m = -1/4
300
Write the equation of the line in slope-intercept form: x intercept = 3, y intercept = -3
y = x - 3
300
Write the equation of a line in point-slope form: m = 7, passes through (-2, 5)
y - 5 = 7(x + 2)
300
Write the equation of the line in standard form: y - 10 = 2(x + 4)
2x - y = -18
300
Is this a direct variation? If yes, find k. If no, tell why not. Mr. McNamee is collecting shark teeth to make charms for his beard. After 7 trips to the beach, he has 28 teeth. After 12 trips, he has 48 teeth.
yes-- k = 4 (4 teeth per trip)
300
Find the equation of a line that is perpendicular to 3x - 4y = 8 and passes through (-6, 5)
y = (-4/3)x - 3
400
Write the equation of a line in slope-intercept form: y - 6 = -3(x + 1)
y = -3x + 3
400
Write an equation for the line in point-slope form: Passes through (4, -2) and (7, 2)
y + 2 = 4/3(x - 4) or y - 2 = 4/3(x - 7)
400
Write the equation of the line in standard form: m = 3/4, passes through (2, 6)
3x - 4y = -18
400
Mr. McNamee is recording changes in the volume of water in Marsha's tank. After 2 minutes, she has 76 cubic inches. After 5 minutes, she has 40 cubic inches. Write an equation in slope-intercept form that models her total volume (y) over time (x) AND identify the meaning of the x intercept, y intercept, and slope.
y = -12x + 100 slope = -12, losing 12 cubic inches per minute y - intercept = 100, she started with 100 cubic inches of water x - intercept = 8 and 1/3, after this many minutes her tank will be empty
400
Write the equation of the line perpendicular to y = 4 and passes through (-5, 4).
x = -5
500
Write the equation of a line in slope-intercept form: Passing through (9, -1) and (2, 13)
y = -2x + 17
500
Write an equation of the line: Passes through (5, -3) and (6, -3)
y = -3 (horizontal line)
500
Write the equation of the line in standard form: Passes through (10, -3) and (8, 3)
3x + y = 27
500
Snowfall accumulates at an average rate of 2.5 inches per hour during a snowstorm. Two hours after the snowstorm begins, the average depth of the snow on the ground is 11 inches. -how much snow is on the ground when the snowfall starts? -The storm begins at 2:15 and continues until 6:30. How much snow is on the ground at the end of the storm? points for each correct answer!
6 inches of snow are already on the ground (this is b) There are 16 and 5/8 inches on the ground at the end of the storm. Stuck? The problem gives you a point (2, 11) and a slope (2.5). Use this to get the equation.
500
Write the equation of the line perpendicular to 5x + 2y = 10 and passes through (3, -5). Slope intercept form!
y = (2/5)x - 6 and 1/5