Function of the Day:
What do you know?
- A linear system of equations consists of two or more equations with the same variables.
- A solution to a system of linear equations is an ordered pair (or tuple) that satisfies all equations in the system.
- The graphs of linear equations in a system can intersect at different points or be parallel (no solution).
- Linear equations can be represented in standard form, slope-intercept form, or point-slope form.
- The number of solutions can be one (intersecting lines), none (parallel lines), or infinitely many (same line).
- Variables are typically represented by letters (e.g., x, y).
- A system of linear equations can be solved using substitution, elimination, or graphing methods.
- A consistent system has at least one solution, while an inconsistent system has no solutions.
- The point of intersection represents the solution in a graphical representation of linear equations.
- Linear equations can model real-world scenarios, such as costs, distances, or populations.
Vocabulary Terms - Define/Illustrate
- Variables: Symbols that represent unknown values in equations (e.g., x, y).
- Linear equation: An equation that forms a straight line when graphed; typically written in the form y = mx + b.
- System of equations: A set of equations with the same variables.
- Solution: A set of values that makes all equations in the system true.
- Intersecting lines: Lines that cross at a point; represent one unique solution.
- Parallel lines: Lines that never intersect; represent no solution.
- Coincident lines: Lines that lie on top of each other; represent infinitely many solutions.
How many variables are in a linear system of equations?
- There can be two or more variables in a linear system of equations, but typically we encounter two (e.g., x and y).
How do you know if you have a linear system of equations?
- A linear system consists of two or more linear equations with the same variables.
What does the solution to a system of linear equations look like?
- The solution is typically represented as an ordered pair (x, y) that satisfies all equations in the system and corresponds to the point of intersection of the graphs of the equations.
5 Problems - SHOW ALL WORK!
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Pizza Cost Problem: Let \( x \) be the number of toppings.
For Palanzio’s Pizza:
Cost = \( 6.80 + 0.90x \)For Guido’s Pizza:
Cost = \( 7.30 + 0.65x \)Set the two equations equal: \[ 6.80 + 0.90x = 7.30 + 0.65x \] Subtract \( 0.65x \) from both sides: \[ 6.80 + 0.25x = 7.30 \] Subtract 6.80 from both sides: \[ 0.25x = 0.50 \] Divide both sides by 0.25: \[ x = 2 \] Solution: Palanzio’s Pizza and Guido’s Pizza will cost the same when there are 2 toppings.
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CD Sales Problem: Let \( l \) = number of CDs sold last week, \( t \) = number of CDs sold this week.
The system of equations:
- \( l = 3t + 6 \) (Last week's sales)
- \( l + t = 110 \) (Total sales)
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Rectangle Dimensions: Let \( l \) = length and \( w \) = width.
Given: \( l = 3w \) (Length is triple the width) The perimeter \( P = 2l + 2w = 86 \).
System of equations:
- \( l = 3w \)
- \( 2l + 2w = 86 \)
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World Series Wins Problem: Let \( y \) = number of World Series won by the Reds, \( x \) = number won by the Yankees.
System of equations:
- \( x + y = 31 \)
- \( x = 5.2y \)
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NFL Earnings Problem: Let \( a \) = Aikman's earnings, \( d \) = Sanders' earnings.
System of equations:
- \( a = d + 0.467 \)
- \( a + d = 12.867 \)
What do I need help with?
- Please identify any specific areas in these topics or problems where you feel confused or need additional clarification!