Graphs 9
3 marks · EasyThe table below gives the values of y for the curve at different points:
| x | y |
|---|---|
| -1 | -1 |
| 0 | 0 |
| 1 | 5 |
| 2 | 14 |
Use the table to estimate the gradient (rate of change) between the points where and . Give your answer in simplest form.
Work this out on paper, then compare with the answer and worked solution below. With a free account you can submit written answers for marking.
Show answer
9
Also accept: The difference in y divided by the difference in x: (14 - 5)/(2 - 1) = 9
Common mistakes: Swapping x and y values in the formula.; Finding an average instead of the gradient.
Show mark scheme and worked solution
Marking points
M1 · 1 mark · Uses the correct gradient formula (change in y / change in x) to set up calculations with table data.
M2 · 1 mark · Substitutes the correct values: (14 - 5) / (2 - 1) or equivalent.
A1 · 1 mark · Final answer is given as 9.
Worked solution
Gradient between the points (1, 5) and (2, 14):