Digits, Grade 8, Volume 1, Homework Helper

8-3: Solving Simultaneous Linear Equations by Graphing

Part 1

Example Solving Systems of Simultaneous Equations by Graphing

Identify the x- and y-values that simultaneously satisfy the two linear equations represented by the graph. Then verify that your values satisfy each equation.

A graph of y = x = 1 and y = 3x − 7.

Solution

The previous graph of y = x + 1 and y = 3x − 7. The solution is the point of intersection, (4, 5).

The lines intersect at (4, 5), so (4, 5) is the solution of the system.

Substitute the x- and y-coordinates of the point into each equation to verify the solution.

table with 3 rows and 4 columns , row1 column 1 , y , column 2 equals x plus 1 , column 3 y , column 4 equals 3 x minus 7 , row2 column 1 , 5 , column 2 modified modified question mark with under bar below with under bar below , 4 plus 1 , column 3 5 , column 4 modified modified question mark with under bar below with under bar below , 3 open 4 close minus 7 , row3 column 1 , 5 , column 2 equals 5 u 2 , column 3 5 , column 4 equals 5 u 2 , end table


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Table of Contents

Digits, Grade 8, Volume 1, Homework Helper Unit A: Number and Operations Unit B: Proportionality Unit C: Expressions, Equations, and Relationships English/Spanish Glossary Formulas Math Symbols Formulas Measures Properties