The Starting Height
Part of the Graphs & Systems section of Coddy's Algebra journey. Lesson 18 of 64.
The y-intercept is where a graph crosses the y-axis. Its x value is always 0. For a line in slope-intercept form, the y-intercept is (0, b). For any other equation, put x = 0 into the equation and work out y.
y = -2x + 3 starts at (0, 3)
In a word problem, the y-intercept is the starting amount. It could be the fee you pay before you travel any distance, or the water level before any water is added. The slope is the rate of change, and the y-intercept is the value when x = 0.
Challenge
MediumA line is drawn. Place the point where it crosses the y-axis.
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 Relations2From Rule to Line
A Rule Makes PointsThe Points Line UpOn the Line or Not?Between the DotsRecap: Rule to Line