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Chapter 4 Section 1. Systems of Equations in two Variables. So, what constitutes a solution? Notice that we have 2 variables and as such we will need 2 values to be a solution. Hence the solutions are ordered pairs. For example, is (1, 2) a solution to the given system?. Your Turn.
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Chapter 4 Section 1 Systems of Equations in two Variables
So, what constitutes a solution? Notice that we have 2 variables and as such we will need 2 values to be a solution. Hence the solutions are ordered pairs. • For example, is (1, 2) a solution to the given system?
Your Turn • Determine if any of the given ordered pairs are solutions to the given system of equations.(0, 3), (1, 5), (2, 7);
How Many Solutions Can You Have? • There were three possible situations that we could get from a system.
One Solution • One Solution at a single point. We say the system is independent.
Infinite Solutions • The equations have the same graph and has an infinite number of solutions. We say the system is dependent.
No Solution • When you solve graphically, you’ll get parallel lines. There are no solutions. Since it is two different equations, it is still independent.
For All Problems in Section 4.1 • Solve both equations for y. That is, write the equation in y = mx + b slope-intercept form. • Put the equations into Y1 and Y2. • Graph the equations and adjust the WINDOW until you see the point of intersection. • Use the INTERSECT routine in the calculator to find the point of intersection. • Make a reasonable sketch of the graph and label your solution on the graph. Use a rule to draw all lines.
Problem Solving • Analyze the problem. • Define your variables and form a system of equations. • Solve the system. • Check the solution. • State the conclusion.
Modeling the Real World • A standard tennis court used for doubles has a perimeter of 228ft. The width is given to be 42ft less than the width. Translate into a system of equations.
Green Diamond Can either convert logs into lumber of plywood. In a given day the mill turns out 42 units of plywood and lumber. It makes a profit of $2500 on a unit of lumber and $4000 on a unit of plywood. How many units of each type were produced if they sold all 42 units and made a profit of $124,500?