Two Lines, One Answer
Part of the Graphs & Systems section of Coddy's Algebra journey. Lesson 49 of 64.
A system asks us to satisfy two or more equations at the same time. Here, both equations are linear, so their graphs are straight lines. A point satisfying both equations lies on both lines. If the lines intersect once, that intersection is the system's only solution.
The crossing (1, 2) solves both equations at once
Check (1, 2) by substituting into both equations. In y = x + 1, we get 2 = 1 + 1. In y = -x + 3, we get 2 = -1 + 3. Both are true, so the point solves the system.
Challenge
MediumTwo lines are drawn. Place the point that solves both of their equations at once.
Test yourselfThis lesson includes a short quiz. Start the lesson to answer it and track your progress.
Test yourselfThis lesson includes a short quiz. Start the lesson to answer it and track your progress.
All lessons in Graphs & Systems
1The Coordinate Plane
Two Numbers, One PointThe Four QuadrantsPoints on the AxesMirror PointsRecap: The Plane4Slope-Intercept Form
y = mx + bThe Starting HeightWrite the EquationSolve for yDraw From Any FormRecap: y = mx + b7Parallel & Perpendicular
Same Slope, Never MeetThe Perpendicular SlopeA Right-Angle LineRecap: Two Relations10Systems by Graphing
Two Lines, One AnswerSolve by DrawingCheck the CrossingWhen Lines Never CrossRecap: By Graphing2From Rule to Line
A Rule Makes PointsThe Points Line UpOn the Line or Not?Between the DotsRecap: Rule to Line