Day 8 Horizontal and Vertical Lines.notebook
October 23, 2015
Warm up:
Write an equation in point‐slope form for the line graphed below.
(6, 14)
(10, 13)
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Day 8 Horizontal and Vertical Lines.notebook
October 23, 2015
Horizontal and Vertical Lines
Warm up:
a) A horizontal line looks like: b) A horizontal line has a slope = _____________
c) Prove that the points (9, ­3) and (­100, ­3) are on a horizontal line by finding the slope.
d) Find the equation for the horizontal line that passes through the point (­7, 13) by plugging the slope and the point into Point­Slope Form. Solve for y so your equation is in slope­intercept form.
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Day 8 Horizontal and Vertical Lines.notebook
October 23, 2015
Notes: HORIZONTAL LINES
The equation of a horizontal line is always The slope of a horizontal line is always ________________
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Day 8 Horizontal and Vertical Lines.notebook
October 23, 2015
Examples:
1. y = 7
2. Given (4, 2), (‐5, 2) and (12, 2) name three other points on the line. ______________________________________
What is the equation of this line? ________________________
What is the y‐intercept of this line? ______________________
What is the slope of this line? ___________________________
3. Write the equation of the line with slope = 0 through (‐4, ‐3). ___________________
4. Find r so that the points (2, 3) and (6, r) are on a line with slope = 0. ______________
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Day 8 Horizontal and Vertical Lines.notebook
October 23, 2015
You try:
1. Write the equation of the line with slope = 0 that passes through the origin. _________
2. a) What is the equation of the line on the graph?
b) What are three other points on the line?
c) What do all three points have in common?
3. Are (‐2, 5) and (‐2, 6) on a horizontal line? Explain how you know.
4. Are (4, 5) and (‐3, 5) on a horizontal line?
Prove it by finding the slope.
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Day 8 Horizontal and Vertical Lines.notebook
October 23, 2015
Notes: VERTICAL LINES
The equation of a vertical line is always The slope of a vertical line is always ________________
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Day 8 Horizontal and Vertical Lines.notebook
October 23, 2015
Examples:
1. x = ‐3
2. Given (15, 0), (15, 2) and (15, ‐12) name three other points on the line. _________________
What is the equation of this line? ________________________
What is the y‐intercept of this line? ______________________
What is the slope of this line? ___________________________
3. Write the equation of the vertical line through (‐4, ‐3). ___________________
4. Find r so that the points (2r, 3) and (6, 11) are on a line with undefined slope. ____________
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Day 8 Horizontal and Vertical Lines.notebook
October 23, 2015
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