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Mindjog 9/1. Given the points (-1, 4) and (2, 8), find: The distance, slope and midpoint The equation of the line passing through the 2 points. OBJECTIVE. SWBAT explore and exhaust all knowledge of linear functions. Linear Functions. Sketch the function f(x) = -(3/4)x + 7.
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Mindjog 9/1 Given the points (-1, 4) and (2, 8), find: • The distance, slope and midpoint • The equation of the line passing through the 2 points
OBJECTIVE • SWBAT • explore and exhaust all knowledge of linear functions
Linear Functions • Sketch the function f(x) = -(3/4)x + 7
Convert the Equation • Find the slope and y-intercept, then sketch. • 3y – 5x = 15 (standard) • -2x – 6y + 15 = 0 (general)
Slope • Describe a • Positive slope • Negative slope • Zero slope • Undefined slope
What if… • The line through the points (-2, 6) and (4, y) has a slope of 3. Find y.
Linear Equations • Given point (-6,4) and slope 1/2, write the equation of the line in slope intercept and general form.
Other Linear Topics • Explain x = -2, and y = 4. • Parallel lines? • Perpendicular lines?
ADMINISTRATIVE STUFF • Syllabus • Parent Survey
Mindjog 9/2 • Write the equation of the line perpendicular to 3x + 7y = 21 but passing through the origin. Sketch both.
MINDJOG 9/3 • A chemist needs a 20% solution of alcohol. She has a 15% solution on hand, as well as a 30% solution. How many liters of the 15% solution should she add to 3L of the 30% solution to obtain her 20% solution?
OBJECTIVE (9/2 and 9/3) • SWBAT • Use applications and models of linear equations (in groups on 9/2)
LINEAR EQUATION • Definition? • Variable to the first degree!
Applications of Linear Functions • If the length of each side of a square is increased by 3cm, the perimeter of the new square is 40cm more than twice the length of each side of the original square. Find the dimensions of the original square.
SOLUTION • 4(x + 3) = 40 + 2x • x = 14
Applications of Linear Functions • A chemist needs a 20% solution of alcohol. She has a 15% solution on hand, as well as a 30% solution. How many liters of the 15% solution should she add to 3L of the 30% solution to obtain her 20% solution?
SOLUTION • .15x+.3(3)=.2(3 + x) • x = 6
Applications of Linear Functions • Maria and Jake are traveling to a business conference. The trip takes 2hrs for Maria and 2.5hrs for Jake, since he lives 40mi farther away. Jake travels 5mph faster than Maria. Find their average rates.
SOLUTION • 2.5(x+5) = 2x + 40 • x = 55
Applications of Linear Functions • An artist has sold a painting for $410,000. He needs some of the money in 6 months and the rest in 1yr. He can get a treasury bond for 6 months at 4.65% and one for a year at 4.91%. His broker tells him the two investments will earn a total of $14,961. How much should be invested at each rate?
SOLUTION • .0465(.5x) + .0491(410,000 – x) = 14,961 • x = 200,000
CLASSWORK (9/3) • Ditto 1.2 Applications and Modeling… • Stand if You Agree
ADMIN (9/2) • Syllabus/Student Survey • Parent Survey
HOMEWORK (9/2) • Textbook, p. 89 #’s 50-60 even • p. 97-100 #’s 2-40 even
HOMEWORK (9/3) • Finish Ditto 1.2 Applications and Modeling…
Mindjog 9/4 Suppose that tuition is $69.69 per credit hour and that student fees are fixed at $25. Antonio paid $1,070.35 for his fall classes. How many credit hours did he sign up for?
CLASSWORK Pair Get to know you