Brainlag PlusRead conversion, distance-time and cost graphs, say what the gradient and intercept mean, and solve simultaneous equations where two lines cross.
Gradient is a rate
On a real-life graph the gradient is a rate: the change in the vertical quantity for each one unit across.
On a distance-time graph that rate is the speed.
- out: 10 km in 30 minutes = 10 km in 0.5 hours
- speed = 10 ÷ 0.5 = 20 km/h
- flat part: 30 to 50 minutes, stopped for 20 minutes
- home: 10 km in 40 minutes, 10 ÷ (40/60) = 15 km/h
Convert the minutes to hours before dividing, or the answer comes out in km per minute.
The rest of this lesson and its 7 practice questions are in Plus.
Screen 1 of 4, free to read.
- 7 exam-style questions, marked as you go, each with a worked solution
- The Graphing Calculator beside every question
- Anything you get wrong is saved to your flashcards