3.14.13
9.9 Systems of Linear Equations in Three Variables
Tuesday, July 17, 2012
10:31 PM
• Ordered Triple:
coordinates in 3-dimensional space.
• Linear Equation in Three Variables: an equation in the form
, where A, B, C, and D are all real numbers and A, B, and
C are not all zero.
Examples:
HA2T-A Page 1
Word Problems:
• Barbara has nickels, dimes, and quarters worth $2.35 in her purse. The
number of dimes is three less than the sum of the number of nickels and
quarters. How many of each type of coin does she have if there are 19 coins in
all?
• A chemist has three samples of unknown mass. Each pair of the samples is
balanced against the third sample and one of three known masses. Find the
unknown masses if the known masses are 9g, 15g, and 27g.
Practice:
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p. 448 #13-18
pp. 448-49 #2, 3, 5-8
Homework: MathXL 9.9 HW
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